Since you are not familiar with programming I would suggest that you not consider using Python. Use an existing well known platform such as MT4/5, Ninjatrader, Tradestation, etc. These platforms have the necessary plumbing, charting and drawing tools, architecture, broker platform connectors, backtesting capabilities, etc. to build on top of. Visit their forums and most likely you will find programmers who have been vetted by the community and can provide you with samples of similar work that they have done for others.
The next step is to write clear requirements for what you want built and get some time estimates and quotes for the same. Ask for a project based quote rather than for hourly rates. I can help you with your requirements document if you like.
I would also look to limit the functionality to the absolute minimum to save on cost for now. Later you can augment what you have and build out the remaining functionality. For example for your EAs you can have them built to merely provide entry/exit alerts instead of executing trades. That way you can save on the cost of building out functionality for programmatic trade management, account management, etc.