My time is limited to focus on this project, I'd be more than happy to hand it over to a dedicated contributor.

API bindings for creating and reading resources in Unleashed Inventory

Authentication is made by signing requests with HMACSHA256 API key/secret available once signed in.

var client = new UnleashedClient("[ApiId]", "[ApiKey]");
foreach (var product in await client.Products.List())
{
    Console.WriteLine(product.ProductDescription);
}

[] (https://ci.appveyor.com/project/ElijahGlover/unleashedapi)

Add-Package UnleashedApi

https://www.nuget.org/packages/UnleashedApi/