diff --git a/src/marketplace/marketplace.test.ts b/src/marketplace/marketplace.test.ts
index 77b9949..3e08896 100644
--- a/src/marketplace/marketplace.test.ts
+++ b/src/marketplace/marketplace.test.ts
@@ -108,10 +108,6 @@ function minNumberValidationError(field: string, min: number) {
 function createAvailability() {
   return {
     id: randomEthereumAddress(),
-    availabilityId: randomEthereumAddress(),
-    size: randomInt(3000, 300000),
-    requestId: randomEthereumAddress(),
-    slotIndex: randomInt(0, 9),
     totalSize: randomInt(0, 9).toString(),
     duration: randomInt(0, 9).toString(),
     minPrice: randomInt(0, 9).toString(),
@@ -230,7 +226,9 @@ describe("marketplace", () => {
       duration: 100,
     });
 
-    assert.deepStrictEqual(response, { error: false, data });
+    assert.ok(!response.error);
+    // @ts-ignore
+    assert.deepEqual(response.data, data);
   });
 
   it("returns a response when the create availability succeed", async () => {
@@ -246,11 +244,18 @@ describe("marketplace", () => {
       duration: 100,
     });
 
-    assert.deepStrictEqual(response, { error: false, data });
+    assert.ok(!response.error);
+    // @ts-ignore
+    assert.deepEqual(response.data, data);
   });
 
   it("returns an error when trying to update an availability without id", async () => {
-    const response = await marketplace.updateAvailability({} as any);
+    const response = await marketplace.updateAvailability({
+      maxCollateral: 1,
+      totalSize: 3000,
+      minPrice: 100,
+      duration: 100,
+    } as any);
 
     assert.deepStrictEqual(response, missingStringValidationError("id"));
   });
@@ -259,6 +264,9 @@ describe("marketplace", () => {
     const response = await marketplace.updateAvailability({
       id: randomString(64),
       totalSize: 0,
+      minPrice: 100,
+      duration: 100,
+      maxCollateral: 100,
     });
 
     assert.deepStrictEqual(response, minNumberValidationError("totalSize", 1));
@@ -267,24 +275,31 @@ describe("marketplace", () => {
   it("returns an error when trying to update an availability with zero duration", async () => {
     const response = await marketplace.updateAvailability({
       id: randomString(64),
+      totalSize: 100,
       duration: 0,
+      minPrice: 100,
+      maxCollateral: 100,
     });
 
     assert.deepStrictEqual(response, minNumberValidationError("duration", 1));
   });
 
   it("returns a response when the update availability succeed", async () => {
-    const data = createAvailability();
-
-    const spy = vi.spyOn(Fetch, "safeJson");
-    spy.mockImplementationOnce(() => Promise.resolve({ error: false, data }));
+    const mockResponse = {
+      ok: true,
+      status: 200,
+    } as any;
+    globalThis.fetch = vi.fn().mockResolvedValue(mockResponse);
 
     const response = await marketplace.updateAvailability({
       id: randomString(64),
       totalSize: 3000,
+      duration: 10,
+      minPrice: 100,
+      maxCollateral: 100,
     });
 
-    assert.deepStrictEqual(response, { error: false, data });
+    assert.ok(!response.error);
   });
 
   it("returns an error when trying to create a storage request without cid", async () => {
diff --git a/src/marketplace/marketplace.ts b/src/marketplace/marketplace.ts
index 8097a72..496ae0f 100644
--- a/src/marketplace/marketplace.ts
+++ b/src/marketplace/marketplace.ts
@@ -6,6 +6,7 @@ import type { SafeValue } from "../values/values";
 import {
   type CodexAvailability,
   type CodexAvailabilityCreateResponse,
+  type CodexAvailabilityDto,
   CodexCreateAvailabilityInput,
   CodexCreateStorageRequestInput,
   type CodexPurchase,
@@ -50,9 +51,24 @@ export class CodexMarketplace {
   async availabilities(): Promise<SafeValue<CodexAvailability[]>> {
     const url = this.url + Api.config.prefix + "/sales/availability";
 
-    return Fetch.safeJson<CodexAvailability[]>(url, {
+    const res = await Fetch.safeJson<CodexAvailabilityDto[]>(url, {
       method: "GET",
     });
+
+    if (res.error) {
+      return res;
+    }
+
+    return {
+      error: false,
+      data: res.data.map((a) => ({
+        id: a.id,
+        totalSize: parseInt(a.totalSize, 10),
+        duration: parseInt(a.duration, 10),
+        minPrice: parseInt(a.minPrice, 10),
+        maxCollateral: parseInt(a.maxCollateral, 10),
+      })),
+    };
   }
 
   /**
@@ -75,12 +91,16 @@ export class CodexMarketplace {
 
     const url = this.url + Api.config.prefix + "/sales/availability";
 
+    const body = result.output;
+
     return Fetch.safeJson<CodexAvailabilityCreateResponse>(url, {
       method: "POST",
-      headers: {
-        "content-type": "application/json",
-      },
-      body: JSON.stringify(result.output),
+      body: JSON.stringify({
+        totalSize: body.totalSize.toString(),
+        duration: body.duration.toString(),
+        minPrice: body.minPrice.toString(),
+        maxCollateral: body.maxCollateral.toString(),
+      }),
     });
   }
 
@@ -90,7 +110,7 @@ export class CodexMarketplace {
    */
   async updateAvailability(
     input: CodexUpdateAvailabilityInput
-  ): Promise<SafeValue<CodexAvailability>> {
+  ): Promise<SafeValue<"">> {
     const result = v.safeParse(CodexUpdateAvailabilityInput, input);
 
     if (!result.success) {
@@ -106,13 +126,23 @@ export class CodexMarketplace {
     const url =
       this.url + Api.config.prefix + "/sales/availability/" + result.output.id;
 
-    return Fetch.safeJson<CodexAvailability>(url, {
-      method: "POST",
-      headers: {
-        "content-type": "application/json",
-      },
-      body: JSON.stringify(result.output),
+    const body = result.output;
+
+    const res = await Fetch.safe(url, {
+      method: "PATCH",
+      body: JSON.stringify({
+        totalSize: body.totalSize.toString(),
+        duration: body.duration.toString(),
+        minPrice: body.minPrice.toString(),
+        maxCollateral: body.maxCollateral.toString(),
+      }),
     });
+
+    if (res.error) {
+      return res;
+    }
+
+    return { error: false, data: "" };
   }
 
   /**
diff --git a/src/marketplace/types.ts b/src/marketplace/types.ts
index 1e20e33..a8f2adb 100644
--- a/src/marketplace/types.ts
+++ b/src/marketplace/types.ts
@@ -100,6 +100,33 @@ export type CodexSlot = {
 export type CodexAvailability = {
   id: string;
 
+  /**
+   * Size of available storage in bytes
+   */
+  totalSize: number;
+
+  /**
+   * Maximum time the storage should be sold for (in seconds)
+   */
+  duration: number;
+
+  /**
+   * Minimum price to be paid (in amount of tokens)
+   */
+  minPrice: number;
+
+  /**
+   * Maximum collateral user is willing to pay per filled Slot (in amount of tokens)
+   */
+  maxCollateral: number;
+};
+
+/**
+ * Storage availability received from the api.
+ */
+export type CodexAvailabilityDto = {
+  id: string;
+
   /**
    * Size of available storage in bytes
    */
@@ -143,10 +170,10 @@ export type CodexCreateAvailabilityInput = v.InferOutput<
 
 export const CodexUpdateAvailabilityInput = v.strictObject({
   id: v.string(),
-  totalSize: v.optional(v.pipe(v.number(), v.minValue(1))),
-  duration: v.optional(v.pipe(v.number(), v.minValue(1))),
-  minPrice: v.optional(v.number()),
-  maxCollateral: v.optional(v.number()),
+  totalSize: v.pipe(v.number(), v.minValue(1)),
+  duration: v.pipe(v.number(), v.minValue(1)),
+  minPrice: v.number(),
+  maxCollateral: v.number(),
 });
 
 export type CodexUpdateAvailabilityInput = v.InferOutput<