You said there was a lot of pressure in the coolant system. How long did you run the car? We need that information to decide if the coolant pressure is normal. If it built up very rapidly, take off the cap on the coolant tank and look for a steady stream of bubbles. If so, probably a blown head gasket.

Also, the system may seem to hold a lot of pressure - when really its not so much pressure, but a larger than expected volume of air. So it makes a big whooossshhh but its not under all that much pressure. If you really are getting too high a coolant pressure, its a bad radiator cap.

The brake rotors will clean up with use. It probably needs glow plugs. All new fluids, etc.

It really sounds like its about a $US1500 car.

Ken300D