You did pay too much for the car. But, you just have to deal mostly with the notorious GP issues that most of us have had to deal with. If they haven't dealt with it, the previous owner did, or they will soon have to deal with it, then their cars won't seem such a good deal. Your car's issues are somewhat cheap to fix. Just takes your time to fix them and the know how to do it.
Plugs and wires - $50
Thermostat - $15 probably fixes whats most likely your heat problem or heater core that would need flushed which is free. Just your time.
Water in the floor board - $2-50 depending on probably the weather stripping fell off and/or leaking sunroof.
Washer fluid pump - $10
Most expensive will be probably a wheel bearing.
Power window motor.... could be a switch, regulator or just the motor. What happens to the defective window when you push the switch? Any sound? All the other windows work?
Anyway's, I bought my GP for $1500 and now have about $3500 in it. Still has issues, but they are minor. Don't feel too bad, most of your problems are cheap to fix, but it just sounds bad with the long list.
