I don't think you're going to get s lot of positive responses to paying that much for a tank screen swap in a DIY forum :-)

If money is a factor, and you don't want to or have the time to work in this vehicle, you really should consider selling it. It will cost a fortune to repair it at a shop or a lot of time.

The shops diagnosis of it either being the tank screen or injectors is not correct - there are a lot of things to check before going there.

I think you have the right idea - find a friendly forum member and pay them 50/hr to straighten things out for you and go from there.