ASP .Net Core Web Application project... Javascript, AJAX, C#, Web API Controllers Sql Server

The project is already in progress. This is to help with the mostly backend part of the application. So no UI work. Must be experienced with asp .net core web applications, Creating models and controllers, Fluent in Javascript and Ajax... (Budget: $250 - $750 USD, Jobs: .NET, ASP.NET, C# Programming, Javascript, Microsoft SQL Server)