I have a P3Pro pro and the image transmission is great sometimes then terrible then if I mess with the flat ribbon cable I can get a good signal again. Is this the camera or the cable? I don't want to buy a new camera if it's just the cable. Also how long should the motors last? I have 352 flights with just over 50 hours flight time. All on the same equipment that I originally bought just under a year ago. Any advice on maintence as to replacing any parts?

Sounds like a bad cable or perhaps connection. Search "phantom 3 pro ribbon cable" on the tube and you'll see lots on cable checking or replacement.
BUT if under a year old would be warranty (wouldn't it ?)
But, if its a simple fix I might be tempted to try myself.
With 352 flights and 50 hours that makes you a Guru

I'd not suggest you to change or replace any parts of the drone by yourself.
I think it's better to send it in and let our engineers to evaluate the drone.