MS Dynamics GP Programmer to maintain interface to my product. My programmer is retiring -- 2

I have a product that is integrated with MS Dynamics using the "dictionary". I have source code and basic instructions for the integration. We currently support the following GP versions: GP10, 2013, 2015. My programmer is ill and will be retiring soon. I need a programmer to maintain the interface between my product and GP as newer versions of GP are released. We will provide the source code and basic interface instructions. My product is a shipping system that prints shipping labels for UPS, FedEx, US Postal and LTL carriers. It has an Microsoft compatible API COM component "EXE" executable that is called from GP Sales Entry screen. After being called my COM API returns a string that has that has the shipping amount and tracking #'s that are posted back to GP order entry screen. Video of my product integrated into GP10 [login to view URL] My product "Freight+" COM API Documentation http:\[login to view URL] I can currently provide the "[login to view URL]" for GP10 and will provide the GP integration documentation as soon as my current programmer provides it to me. Sometime in the next few weeks. I'm looking for a GP programmer that can work with me on all future builds. We will give you an demonstration of our product working with GP and install our product on your workstation or sever so you can do integration. Review the video and COM API documentation and contact me with your qualifications and give me an idea of what you would charge to maintain each build. I can tell you I currently pay $900 per build. The programmer basically copies the code between the builds, creates the dictionary and then installs the new build on my server and I run tests to ensure everything is still working correctly. Thank you, Gary