diff --git a/Streetwriters.Common/Models/ListPaymentsResponse.cs b/Streetwriters.Common/Models/ListPaymentsResponse.cs
new file mode 100644
index 0000000..1703a84
--- /dev/null
+++ b/Streetwriters.Common/Models/ListPaymentsResponse.cs
@@ -0,0 +1,41 @@
+using System;
+using System.Text.Json.Serialization;
+
+namespace Streetwriters.Common.Models
+{
+    public partial class ListPaymentsResponse
+    {
+        [JsonPropertyName("success")]
+        public bool Success { get; set; }
+
+        [JsonPropertyName("response")]
+        public Payment[] Payments { get; set; }
+    }
+
+    public partial class Payment
+    {
+        [JsonPropertyName("id")]
+        public long Id { get; set; }
+
+        [JsonPropertyName("subscription_id")]
+        public long SubscriptionId { get; set; }
+
+        [JsonPropertyName("amount")]
+        public double Amount { get; set; }
+
+        [JsonPropertyName("currency")]
+        public string Currency { get; set; }
+
+        [JsonPropertyName("payout_date")]
+        public string PayoutDate { get; set; }
+
+        [JsonPropertyName("is_paid")]
+        public short IsPaid { get; set; }
+
+        [JsonPropertyName("is_one_off_charge")]
+        public bool IsOneOffCharge { get; set; }
+
+        [JsonPropertyName("receipt_url")]
+        public string ReceiptUrl { get; set; }
+    }
+}
diff --git a/Streetwriters.Common/Models/ListTransactionsResponse.cs b/Streetwriters.Common/Models/ListTransactionsResponse.cs
new file mode 100644
index 0000000..9379eb7
--- /dev/null
+++ b/Streetwriters.Common/Models/ListTransactionsResponse.cs
@@ -0,0 +1,77 @@
+namespace Streetwriters.Common.Models
+{
+    using System;
+    using System.Text.Json.Serialization;
+
+    public partial class ListTransactionsResponse
+    {
+        [JsonPropertyName("success")]
+        public bool Success { get; set; }
+
+        [JsonPropertyName("response")]
+        public Transaction[] Transactions { get; set; }
+    }
+
+    public partial class Transaction
+    {
+        [JsonPropertyName("order_id")]
+        public string OrderId { get; set; }
+
+        [JsonPropertyName("checkout_id")]
+        public string CheckoutId { get; set; }
+
+        [JsonPropertyName("amount")]
+        public string Amount { get; set; }
+
+        [JsonPropertyName("currency")]
+        public string Currency { get; set; }
+
+        [JsonPropertyName("status")]
+        public string Status { get; set; }
+
+        [JsonPropertyName("created_at")]
+        public string CreatedAt { get; set; }
+
+        [JsonPropertyName("passthrough")]
+        public object Passthrough { get; set; }
+
+        [JsonPropertyName("product_id")]
+        public long ProductId { get; set; }
+
+        [JsonPropertyName("is_subscription")]
+        public bool IsSubscription { get; set; }
+
+        [JsonPropertyName("is_one_off")]
+        public bool IsOneOff { get; set; }
+
+        [JsonPropertyName("subscription")]
+        public PaddleSubscription Subscription { get; set; }
+
+        [JsonPropertyName("user")]
+        public PaddleTransactionUser User { get; set; }
+
+        [JsonPropertyName("receipt_url")]
+        public string ReceiptUrl { get; set; }
+    }
+
+    public partial class PaddleSubscription
+    {
+        [JsonPropertyName("subscription_id")]
+        public long SubscriptionId { get; set; }
+
+        [JsonPropertyName("status")]
+        public string Status { get; set; }
+    }
+
+    public partial class PaddleTransactionUser
+    {
+        [JsonPropertyName("user_id")]
+        public long UserId { get; set; }
+
+        [JsonPropertyName("email")]
+        public string Email { get; set; }
+
+        [JsonPropertyName("marketing_consent")]
+        public bool MarketingConsent { get; set; }
+    }
+}
diff --git a/Streetwriters.Common/Models/ListUsersResponse.cs b/Streetwriters.Common/Models/ListUsersResponse.cs
new file mode 100644
index 0000000..f0b1c0a
--- /dev/null
+++ b/Streetwriters.Common/Models/ListUsersResponse.cs
@@ -0,0 +1,47 @@
+using System;
+using System.Text.Json.Serialization;
+
+namespace Streetwriters.Common.Models
+{
+    public partial class ListUsersResponse
+    {
+        [JsonPropertyName("success")]
+        public bool Success { get; set; }
+
+        [JsonPropertyName("response")]
+        public PaddleUser[] Users { get; set; }
+    }
+
+    public class PaddleUser
+    {
+        [JsonPropertyName("subscription_id")]
+        public long SubscriptionId { get; set; }
+
+        [JsonPropertyName("plan_id")]
+        public long PlanId { get; set; }
+
+        [JsonPropertyName("user_id")]
+        public long UserId { get; set; }
+
+        [JsonPropertyName("user_email")]
+        public string UserEmail { get; set; }
+
+        [JsonPropertyName("marketing_consent")]
+        public bool MarketingConsent { get; set; }
+
+        [JsonPropertyName("update_url")]
+        public string UpdateUrl { get; set; }
+
+        [JsonPropertyName("cancel_url")]
+        public string CancelUrl { get; set; }
+
+        [JsonPropertyName("state")]
+        public string State { get; set; }
+
+        [JsonPropertyName("signup_date")]
+        public string SignupDate { get; set; }
+
+        [JsonPropertyName("quantity")]
+        public long Quantity { get; set; }
+    }
+}
diff --git a/Streetwriters.Common/Models/RefundPaymentResponse.cs b/Streetwriters.Common/Models/RefundPaymentResponse.cs
new file mode 100644
index 0000000..d74a294
--- /dev/null
+++ b/Streetwriters.Common/Models/RefundPaymentResponse.cs
@@ -0,0 +1,20 @@
+using System;
+using System.Text.Json.Serialization;
+
+namespace Streetwriters.Common.Models
+{
+    public partial class RefundPaymentResponse
+    {
+        [JsonPropertyName("success")]
+        public bool Success { get; set; }
+
+        [JsonPropertyName("response")]
+        public Refund Refund { get; set; }
+    }
+
+    public partial class Refund
+    {
+        [JsonPropertyName("refund_request_id")]
+        public long RefundRequestId { get; set; }
+    }
+}
diff --git a/Streetwriters.Common/Services/PaddleService.cs b/Streetwriters.Common/Services/PaddleService.cs
new file mode 100644
index 0000000..1ab9801
--- /dev/null
+++ b/Streetwriters.Common/Services/PaddleService.cs
@@ -0,0 +1,188 @@
+using System;
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Net.Http.Json;
+using System.Text.Json.Serialization;
+using System.Threading.Tasks;
+using Streetwriters.Common.Models;
+
+namespace Streetwriters.Common.Services
+{
+    public class PaddleService(string vendorId, string vendorAuthCode)
+    {
+#if (DEBUG || STAGING)
+        const string PADDLE_BASE_URI = "https://sandbox-vendors.paddle.com/api";
+#else
+        const string PADDLE_BASE_URI = "https://vendors.paddle.com/api";
+#endif
+
+        HttpClient httpClient = new HttpClient();
+
+        public async Task<ListUsersResponse> ListUsersAsync(
+            string subscriptionId,
+            int results
+        )
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/subscription/users";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                        { "subscription_id", subscriptionId },
+                        { "results_per_page", results.ToString() },
+                    }
+                )
+            );
+
+            return await response.Content.ReadFromJsonAsync<ListUsersResponse>();
+        }
+
+        public async Task<ListPaymentsResponse> ListPaymentsAsync(
+            string subscriptionId,
+            long planId
+        )
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/subscription/payments";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                        { "subscription_id", subscriptionId },
+                        { "is_paid", "1" },
+                        { "plan", planId.ToString() },
+                        { "is_one_off_charge", "0" },
+                    }
+                )
+            );
+
+            return await response.Content.ReadFromJsonAsync<ListPaymentsResponse>();
+        }
+
+        public async Task<ListTransactionsResponse> ListTransactionsAsync(
+            string subscriptionId
+        )
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/subscription/{subscriptionId}/transactions";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                    }
+                )
+            );
+
+            return await response.Content.ReadFromJsonAsync<ListTransactionsResponse>();
+        }
+
+        public async Task<PaddleTransactionUser> FindUserFromOrderAsync(string orderId)
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/order/{orderId}/transactions";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                    }
+                )
+            );
+            var transactions = await response.Content.ReadFromJsonAsync<ListTransactionsResponse>();
+            if (transactions.Transactions.Length == 0) return null;
+            return transactions.Transactions[0].User;
+        }
+
+        public async Task<bool> RefundPaymentAsync(string paymentId, string reason = "")
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/payment/refund";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                        { "order_id", paymentId },
+                        { "reason", reason },
+                    }
+                )
+            );
+
+            var refundResponse = await response.Content.ReadFromJsonAsync<RefundPaymentResponse>();
+            return refundResponse.Success;
+        }
+
+        public async Task<bool> CancelSubscriptionAsync(string subscriptionId)
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/subscription/users_cancel";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                        { "subscription_id", subscriptionId },
+                    }
+                )
+            );
+
+            return response.IsSuccessStatusCode;
+        }
+
+        public async Task<bool> PauseSubscriptionAsync(string subscriptionId)
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/subscription/users/update";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                        { "subscription_id", subscriptionId },
+                        { "pause", "true" },
+                    }
+                )
+            );
+
+            return response.IsSuccessStatusCode;
+        }
+
+        public async Task<bool> ResumeSubscriptionAsync(string subscriptionId)
+        {
+            var url = $"{PADDLE_BASE_URI}/2.0/subscription/users/update";
+            var httpClient = new HttpClient();
+            var response = await httpClient.PostAsync(
+                url,
+                new FormUrlEncodedContent(
+                    new Dictionary<string, string>
+                    {
+                        { "vendor_id", vendorId },
+                        { "vendor_auth_code", vendorAuthCode },
+                        { "subscription_id", subscriptionId },
+                        { "pause", "false" },
+                    }
+                )
+            );
+
+            return response.IsSuccessStatusCode;
+        }
+    }
+}