Mock sample for your project: Qualpay Payment Gateway API

https://www.beanstream.com/api/v1

Service for providing information to sellers about their listings being non-compliant, or at risk for becoming non-compliant, against eBay listing policies.

Use the Fulfillment API to complete the process of packaging, addressing, handling, and shipping each order on behalf of the seller, in accordance with the payment method and timing specified at checkout.

Documentation of the Billbee REST API to connect a Billbee account to external aplications.
Endpoint
The Billbee API endpoint base url is https://app.billbee.io/api/v1
Activation
You have to enable the API in the settings of your Billbee account. In addition you need a Billbee API Key identifying the application you develop. To get an API key, send a mail to [email protected] and send us a short note about what you are building.
Authorization & security
Because you can access private data with the Billbee API, every request has to be sent over https and must
Contain a valid API Key identifying the application/developer. It has to be sent as the HTTP header X-Billbee-Api-Key
Contain a valid user login with billbee username and api password in form of a basic auth HTTP header
Throttling
Each endpoint has a throttle of max 2 requests per second per combination of API Key and Billbee user.
When you exceed these 2 calls, the API will return a HTTP 429 status code

dropX.io API provides programmatic access to the e-commerce intelligence data.

Note: This is a (Limited Release) API available only to select developers approved by business units. The Logistics API resources offer the following capabilities: shipping_quote – Consolidates into a list a set of live shipping rates, or quotes, from which you can select a rate to ship a package. shipment – Creates a "shipment" for the selected shipping rate. Call createShippingQuote to get a list of live shipping rates. The rates returned are all valid for a specific time window and all quoted prices are at eBay-negotiated rates. Select one of the live rates and using its associated rateId, create a "shipment" for the package by calling createFromShippingQuote. Creating a shipment completes an agreement, and the cost of the base service and any added shipping options are summed into the returned totalShippingCost value. This action also generates a shipping label that you can use to ship the package. The total cost of the shipment is incurred when the package is shipped using the supplied shipping label. Important! Sellers must set up a payment method via their eBay account before they can use the methods in this API to create a shipment and the associated shipping label.

The Marketing API retrieves eBay products based on a metric, such as Best Selling, as well as products that were also bought and also viewed.

The Charity API allows third-party developers to search for and access details on supported charitable organizations.

Endpoint Structure
All URLs are in the format:
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Please make sure you use the correct version of the APIs for your use case. To find out the appropriate version, go to the API Docs drop down on the menu.

The Account API gives sellers the ability to configure their eBay seller accounts, including the seller's policies (the Fulfillment Policy, Payment Policy, and Return Policy), opt in and out of eBay seller programs, configure sales tax tables, and get account information. For details on the availability of the methods in this API, see Account API requirements and restrictions.