I have 1.0 code of Shopify plug in as well as WooCommerce plug in, which lets my customers (eCommerce store owners) negotiate prices with their buyers through my plug in. I have it working in couple of sites. As I have seen some inconsistencies store to store, I need someone to manage these plug ins and help me with FIXING minor issues/bug fixes. I am expecting 10 hours/ month for my budget.
Budget is for both platforms. I will share code base/online access for hosting that I have.