diff --git a/erpnext/assets/doctype/asset_repair/asset_repair.js b/erpnext/assets/doctype/asset_repair/asset_repair.js
index f09f2fe2e17..bdbf60f653e 100644
--- a/erpnext/assets/doctype/asset_repair/asset_repair.js
+++ b/erpnext/assets/doctype/asset_repair/asset_repair.js
@@ -117,25 +117,52 @@ frappe.ui.form.on("Asset Repair", {
 			frm.refresh_field("stock_items");
 		}
 	},
+});
 
-	purchase_invoice: function (frm) {
-		if (frm.doc.purchase_invoice) {
-			frappe.call({
-				method: "frappe.client.get_value",
-				args: {
-					doctype: "Purchase Invoice",
-					fieldname: "base_net_total",
-					filters: { name: frm.doc.purchase_invoice },
-				},
-				callback: function (r) {
-					if (r.message) {
-						frm.set_value("repair_cost", r.message.base_net_total);
-					}
-				},
-			});
-		} else {
-			frm.set_value("repair_cost", 0);
+frappe.ui.form.on("Asset Repair Purchase Invoice", {
+	purchase_invoice: function (frm, cdt, cdn) {
+		frappe.model.set_value(cdt, cdn, {
+			expense_account: "",
+			repair_cost: 0,
+		});
+	},
+
+	expense_account: function (frm, cdt, cdn) {
+		let row = locals[cdt][cdn];
+
+		if (!row.purchase_invoice || !row.expense_account) {
+			frappe.model.set_value(cdt, cdn, "repair_cost", 0);
+			return;
 		}
+
+		frappe.call({
+			method: "erpnext.assets.doctype.asset_repair.asset_repair.get_unallocated_repair_cost",
+			args: {
+				purchase_invoice: row.purchase_invoice,
+				expense_account: row.expense_account,
+			},
+			callback: function (r) {
+				if (r.message !== undefined) {
+					if (r.message > 0) {
+						frappe.model.set_value(cdt, cdn, "repair_cost", r.message);
+					} else {
+						frappe.model.set_value(cdt, cdn, "repair_cost", 0);
+						let pi_link = frappe.utils.get_form_link(
+							"Purchase Invoice",
+							row.purchase_invoice,
+							true
+						);
+						frappe.msgprint({
+							message: __(
+								"Row {0}: The entire expense amount for account {1} in {2} has already been allocated.",
+								[row.idx, row.expense_account.bold(), pi_link]
+							),
+							indicator: "orange",
+						});
+					}
+				}
+			},
+		});
 	},
 
 	show_general_ledger: (frm) => {
diff --git a/erpnext/assets/doctype/asset_repair/asset_repair.py b/erpnext/assets/doctype/asset_repair/asset_repair.py
index 5c280404958..476b0187bf1 100644
--- a/erpnext/assets/doctype/asset_repair/asset_repair.py
+++ b/erpnext/assets/doctype/asset_repair/asset_repair.py
@@ -4,6 +4,7 @@
 import frappe
 from frappe import _
 from frappe.query_builder import DocType
+from frappe.query_builder.functions import Sum
 from frappe.utils import cint, flt, get_link_to_form, getdate, time_diff_in_hours
 
 import erpnext
@@ -14,7 +15,6 @@ from erpnext.accounts.general_ledger import make_gl_entries
 from erpnext.assets.doctype.asset.asset import get_asset_account
 from erpnext.assets.doctype.asset_activity.asset_activity import add_asset_activity
 from erpnext.assets.doctype.asset_depreciation_schedule.asset_depreciation_schedule import (
-	get_depr_schedule,
 	reschedule_depreciation,
 )
 from erpnext.controllers.accounts_controller import AccountsController
@@ -59,7 +59,7 @@ class AssetRepair(AccountsController):
 	# end: auto-generated types
 
 	def validate(self):
-		self.asset_doc = frappe.get_doc("Asset", self.asset)
+		self.asset_doc = frappe.get_lazy_doc("Asset", self.asset)
 		self.validate_asset()
 		self.validate_dates()
 		self.validate_purchase_invoices()
@@ -84,60 +84,91 @@ class AssetRepair(AccountsController):
 			)
 
 	def validate_purchase_invoices(self):
+		self.validate_duplicate_purchase_invoices()
+		self.validate_purchase_invoice_status()
+
 		for d in self.invoices:
-			self.validate_purchase_invoice_status(d.purchase_invoice)
-			invoice_items = self.get_invoice_items(d.purchase_invoice)
-			self.validate_service_purchase_invoice(d.purchase_invoice, invoice_items)
-			self.validate_expense_account(d, invoice_items)
-			self.validate_purchase_invoice_repair_cost(d, invoice_items)
+			self.validate_expense_account(d)
+			self.validate_purchase_invoice_repair_cost(d)
 
-	def validate_purchase_invoice_status(self, purchase_invoice):
-		docstatus = frappe.db.get_value("Purchase Invoice", purchase_invoice, "docstatus")
-		if docstatus == 0:
-			frappe.throw(
-				_("{0} is still in Draft. Please submit it before saving the Asset Repair.").format(
-					get_link_to_form("Purchase Invoice", purchase_invoice)
-				)
+	def validate_duplicate_purchase_invoices(self):
+		# account wise duplicate check
+		purchase_invoices = set()
+		duplicates = []
+		for row in self.invoices:
+			key = (row.purchase_invoice, row.expense_account)
+			if key in purchase_invoices:
+				duplicates.append((row.idx, row.purchase_invoice, row.expense_account))
+			else:
+				purchase_invoices.add(key)
+
+		if duplicates:
+			duplicate_links = "".join(
+				[
+					f"<li>{_('Row #{0}:').format(idx)} {get_link_to_form('Purchase Invoice', pi)} - {frappe.bold(account)}</li>"
+					for idx, pi, account in duplicates
+				]
 			)
+			msg = _("The following rows are duplicates:") + f"<br><ul>{duplicate_links}</ul>"
+			frappe.throw(msg)
 
-	def get_invoice_items(self, pi):
-		invoice_items = frappe.get_all(
-			"Purchase Invoice Item",
-			filters={"parent": pi},
-			fields=["item_code", "expense_account", "base_net_amount"],
+	def validate_purchase_invoice_status(self):
+		pi_names = [row.purchase_invoice for row in self.invoices]
+		docstatus = frappe._dict(
+			frappe.db.get_all(
+				"Purchase Invoice",
+				filters={"name": ["in", pi_names]},
+				fields=["name", "docstatus"],
+				as_list=True,
+			)
 		)
 
-		return invoice_items
+		invalid_invoice = []
+		for row in self.invoices:
+			if docstatus.get(row.purchase_invoice) != 1:
+				invalid_invoice.append((row.idx, row.purchase_invoice))
 
-	def validate_service_purchase_invoice(self, purchase_invoice, invoice_items):
-		service_item_exists = False
-		for item in invoice_items:
-			if frappe.db.get_value("Item", item.item_code, "is_stock_item") == 0:
-				service_item_exists = True
-				break
+		if invalid_invoice:
+			invoice_links = "".join(
+				[
+					f"<li>{_('Row #{0}:').format(idx)} {get_link_to_form('Purchase Invoice', pi)}</li>"
+					for idx, pi in invalid_invoice
+				]
+			)
+			msg = _("The following Purchase Invoices are not submitted:") + f"<br><ul>{invoice_links}</ul>"
+			frappe.throw(msg)
 
-		if not service_item_exists:
+	def validate_expense_account(self, row):
+		"""Validate that the expense account exists in the purchase invoice for non-stock items."""
+		valid_accounts = _get_expense_accounts_for_purchase_invoice(row.purchase_invoice)
+		if row.expense_account not in valid_accounts:
 			frappe.throw(
-				_("Service item not present in Purchase Invoice {0}").format(
-					get_link_to_form("Purchase Invoice", purchase_invoice)
+				_(
+					"Row #{0}: Expense account {1} is not valid for Purchase Invoice {2}. "
+					"Only expense accounts from non-stock items are allowed."
+				).format(
+					row.idx,
+					frappe.bold(row.expense_account),
+					get_link_to_form("Purchase Invoice", row.purchase_invoice),
 				)
 			)
 
-	def validate_expense_account(self, row, invoice_items):
-		pi_expense_accounts = set([item.expense_account for item in invoice_items])
-		if row.expense_account not in pi_expense_accounts:
-			frappe.throw(
-				_("Expense account {0} not present in Purchase Invoice {1}").format(
-					row.expense_account, get_link_to_form("Purchase Invoice", row.purchase_invoice)
-				)
-			)
+	def validate_purchase_invoice_repair_cost(self, row):
+		"""Validate that repair cost doesn't exceed available amount."""
+		available_amount = get_unallocated_repair_cost(
+			row.purchase_invoice, row.expense_account, exclude_asset_repair=self.name
+		)
 
-	def validate_purchase_invoice_repair_cost(self, row, invoice_items):
-		pi_net_total = sum([flt(item.base_net_amount) for item in invoice_items])
-		if flt(row.repair_cost) > pi_net_total:
+		if flt(row.repair_cost) > available_amount:
 			frappe.throw(
-				_("Repair cost cannot be greater than purchase invoice base net total {0}").format(
-					pi_net_total
+				_(
+					"Row #{0}: Repair cost {1} exceeds available amount {2} for Purchase Invoice {3} and Account {4}"
+				).format(
+					row.idx,
+					frappe.bold(frappe.format_value(row.repair_cost, {"fieldtype": "Currency"})),
+					frappe.bold(frappe.format_value(available_amount, {"fieldtype": "Currency"})),
+					get_link_to_form("Purchase Invoice", row.purchase_invoice),
+					frappe.bold(row.expense_account),
 				)
 			)
 
@@ -199,7 +230,7 @@ class AssetRepair(AccountsController):
 		self.cancel_sabb()
 
 	def after_delete(self):
-		frappe.get_doc("Asset", self.asset).set_status()
+		frappe.get_lazy_doc("Asset", self.asset).set_status()
 
 	def check_repair_status(self):
 		if self.repair_status == "Pending" and self.docstatus == 1:
@@ -341,7 +372,10 @@ class AssetRepair(AccountsController):
 			return
 
 		# creating GL Entries for each row in Stock Items based on the Stock Entry created for it
-		stock_entry = frappe.get_doc("Stock Entry", {"asset_repair": self.name})
+		stock_entry_name = frappe.db.get_value("Stock Entry", {"asset_repair": self.name}, "name")
+		stock_entry_items = frappe.get_all(
+			"Stock Entry Detail", filters={"parent": stock_entry_name}, fields=["expense_account", "amount"]
+		)
 
 		default_expense_account = None
 		if not erpnext.is_perpetual_inventory_enabled(self.company):
@@ -351,7 +385,7 @@ class AssetRepair(AccountsController):
 			if not default_expense_account:
 				frappe.throw(_("Please set default Expense Account in Company {0}").format(self.company))
 
-		for item in stock_entry.items:
+		for item in stock_entry_items:
 			if flt(item.amount) > 0:
 				gl_entries.append(
 					self.get_gl_dict(
@@ -382,7 +416,7 @@ class AssetRepair(AccountsController):
 							"cost_center": self.cost_center,
 							"posting_date": self.completion_date,
 							"against_voucher_type": "Stock Entry",
-							"against_voucher": stock_entry.name,
+							"against_voucher": stock_entry_name,
 							"company": self.company,
 						},
 						item=self,
@@ -420,33 +454,152 @@ def get_downtime(failure_date, completion_date):
 
 
 @frappe.whitelist()
+@frappe.validate_and_sanitize_search_inputs
 def get_purchase_invoice(doctype, txt, searchfield, start, page_len, filters):
-	PurchaseInvoice = DocType("Purchase Invoice")
-	PurchaseInvoiceItem = DocType("Purchase Invoice Item")
-	Item = DocType("Item")
+	"""
+	Get Purchase Invoices that have expense accounts for non-stock items.
+	Only returns invoices with at least one non-stock, non-fixed-asset item with an expense account.
+	"""
+	pi = DocType("Purchase Invoice")
+	pi_item = DocType("Purchase Invoice Item")
+	item = DocType("Item")
 
-	return (
-		frappe.qb.from_(PurchaseInvoice)
-		.join(PurchaseInvoiceItem)
-		.on(PurchaseInvoiceItem.parent == PurchaseInvoice.name)
-		.join(Item)
-		.on(Item.name == PurchaseInvoiceItem.item_code)
-		.select(PurchaseInvoice.name)
+	query = (
+		frappe.qb.from_(pi)
+		.join(pi_item)
+		.on(pi_item.parent == pi.name)
+		.left_join(item)
+		.on(item.name == pi_item.item_code)
+		.select(pi.name)
+		.distinct()
 		.where(
-			(Item.is_stock_item == 0)
-			& (Item.is_fixed_asset == 0)
-			& (PurchaseInvoice.company == filters.get("company"))
-			& (PurchaseInvoice.docstatus == 1)
+			(pi.company == filters.get("company"))
+			& (pi.docstatus == 1)
+			& (pi_item.is_fixed_asset == 0)
+			& (pi_item.expense_account.isnotnull())
+			& (pi_item.expense_account != "")
+			& ((pi_item.item_code.isnull()) | (item.is_stock_item == 0))
 		)
-	).run(as_list=1)
+	)
+
+	if txt:
+		query = query.where(pi.name.like(f"%{txt}%"))
+
+	return query.run(as_list=1)
 
 
 @frappe.whitelist()
+@frappe.validate_and_sanitize_search_inputs
 def get_expense_accounts(doctype, txt, searchfield, start, page_len, filters):
-	PurchaseInvoiceItem = DocType("Purchase Invoice Item")
-	return (
-		frappe.qb.from_(PurchaseInvoiceItem)
-		.select(PurchaseInvoiceItem.expense_account)
-		.distinct()
-		.where(PurchaseInvoiceItem.parent == filters.get("purchase_invoice"))
-	).run(as_list=1)
+	"""
+	Get expense accounts for non-stock (service) items from the purchase invoice.
+	Used as a query function for link fields.
+	"""
+	purchase_invoice = filters.get("purchase_invoice")
+	if not purchase_invoice:
+		return []
+
+	expense_accounts = _get_expense_accounts_for_purchase_invoice(purchase_invoice)
+
+	return [[account] for account in expense_accounts]
+
+
+def _get_expense_accounts_for_purchase_invoice(purchase_invoice: str) -> list[str]:
+	"""
+	Get expense accounts for non-stock items from the purchase invoice.
+	"""
+	pi_items = frappe.db.get_all(
+		"Purchase Invoice Item",
+		filters={"parent": purchase_invoice},
+		fields=["item_code", "expense_account", "is_fixed_asset"],
+	)
+
+	if not pi_items:
+		return []
+
+	# Get list of stock item codes from the invoice
+	item_codes = {item.item_code for item in pi_items if item.item_code}
+	stock_items = set()
+	if item_codes:
+		stock_items = set(
+			frappe.db.get_all(
+				"Item", filters={"name": ["in", list(item_codes)], "is_stock_item": 1}, pluck="name"
+			)
+		)
+
+	expense_accounts = set()
+
+	for item in pi_items:
+		# Skip stock items - they use warehouse accounts
+		if item.item_code and item.item_code in stock_items:
+			continue
+
+		# Skip fixed assets - they use asset accounts
+		if item.is_fixed_asset:
+			continue
+
+		# Use expense account from Purchase Invoice Item
+		if item.expense_account:
+			expense_accounts.add(item.expense_account)
+
+	return list(expense_accounts)
+
+
+@frappe.whitelist()
+def get_unallocated_repair_cost(
+	purchase_invoice: str, expense_account: str, exclude_asset_repair: str | None = None
+) -> float:
+	"""
+	Calculate the unused repair cost for a purchase invoice and expense account.
+	"""
+	if not purchase_invoice or not expense_account:
+		return 0.0
+
+	frappe.has_permission("Purchase Invoice", "read", purchase_invoice, throw=True)
+
+	used_amount = get_allocated_repair_cost(purchase_invoice, expense_account, exclude_asset_repair)
+	total_amount = get_total_expense_amount(purchase_invoice, expense_account)
+
+	return flt(total_amount - used_amount)
+
+
+def get_allocated_repair_cost(
+	purchase_invoice: str, expense_account: str, exclude_asset_repair: str | None = None
+) -> float:
+	"""Get the total repair cost already allocated from submitted Asset Repairs."""
+	asset_repair_pi = DocType("Asset Repair Purchase Invoice")
+
+	query = (
+		frappe.qb.from_(asset_repair_pi)
+		.select(Sum(asset_repair_pi.repair_cost).as_("total"))
+		.where(
+			(asset_repair_pi.purchase_invoice == purchase_invoice)
+			& (asset_repair_pi.expense_account == expense_account)
+			& (asset_repair_pi.docstatus == 1)
+		)
+	)
+
+	if exclude_asset_repair:
+		query = query.where(asset_repair_pi.parent != exclude_asset_repair)
+
+	result = query.run(as_dict=True)
+
+	return flt(result[0].total) if result else 0.0
+
+
+def get_total_expense_amount(purchase_invoice: str, expense_account: str) -> float:
+	"""Get the total expense amount from GL entries for a purchase invoice and account."""
+	gl_entry = DocType("GL Entry")
+
+	result = (
+		frappe.qb.from_(gl_entry)
+		.select((Sum(gl_entry.debit) - Sum(gl_entry.credit)).as_("total"))
+		.where(
+			(gl_entry.voucher_type == "Purchase Invoice")
+			& (gl_entry.voucher_no == purchase_invoice)
+			& (gl_entry.account == expense_account)
+			& (gl_entry.is_cancelled == 0)
+		)
+	).run(as_dict=True)
+
+	return flt(result[0].total) if result else 0.0
diff --git a/erpnext/assets/doctype/asset_repair/test_asset_repair.py b/erpnext/assets/doctype/asset_repair/test_asset_repair.py
index e9d603e2267..15ceb51648b 100644
--- a/erpnext/assets/doctype/asset_repair/test_asset_repair.py
+++ b/erpnext/assets/doctype/asset_repair/test_asset_repair.py
@@ -175,6 +175,39 @@ class TestAssetRepair(IntegrationTestCase):
 		)
 		self.assertTrue(asset_repair.invoices)
 
+	def test_repair_cost_exceeds_available_amount(self):
+		"""Test that repair cost cannot exceed available amount from Purchase Invoice."""
+		asset_repair1 = create_asset_repair(
+			capitalize_repair_cost=1,
+			item="_Test Non Stock Item",
+			submit=1,
+		)
+
+		pi_name = asset_repair1.invoices[0].purchase_invoice
+		expense_account = asset_repair1.invoices[0].expense_account
+
+		asset_repair2 = frappe.new_doc("Asset Repair")
+		asset_repair2.update(
+			{
+				"asset": asset_repair1.asset,
+				"asset_name": asset_repair1.asset_name,
+				"failure_date": nowdate(),
+				"description": "Second Repair",
+				"company": asset_repair1.company,
+				"capitalize_repair_cost": 1,
+			}
+		)
+		asset_repair2.append(
+			"invoices",
+			{
+				"purchase_invoice": pi_name,
+				"expense_account": expense_account,
+				"repair_cost": 10,  # PI already fully used, so this should fail
+			},
+		)
+
+		self.assertRaises(frappe.ValidationError, asset_repair2.save)
+
 	def test_gl_entries_with_perpetual_inventory(self):
 		set_depreciation_settings_in_company(company="_Test Company with perpetual inventory")