Hi there,
I read your project and it is interesting. Interactive Broker's API is quite simple to implement, being this integration for quote reading or order management, I even would say they contain one of the best architecture and stable trading API out there (I have tested a lot of APIs).
In your particular case, I can build a very sleek solution to handle all your trading activities to send buy/sell orders, SL/TP orders, etc automatically by only evaluate the price action received by the API. This app will contain a monitor screen where you will see all signals produced and sent to the IB API.
Regarding the back-testing capability, well, I don't think the budget you posted could cover such a development, I've built back-testing systems and these are not necessarily a walk in the park, even though if you consider to increase your budget to ~$500USD, then I may send you some samples of a back testing app I built in C# some time ago. This back testing app have the ability to load a custom strategy, custom indicators, retrieve quotes from database and test any period you need to. What makes this back-testing app different from the others, because there are plenty of them on internet, is that this one can use the real Depth of Market in the tests, this means that you could create your strategy to evaluate the Depth of Market and trade accordingly. For some traders, having a back-test with the Depth of Market makes the difference.
Regards,
Eng. John P.