for what you paid fella it looks a good base for a project. as for the leaking, check the rear lights, and around the rear window, as a first port of call.
anything you get stuck with, give me a shout, and if i cant help, i know plenty of people who can.
might be an idea to register at the mondeo forum in my signature, very helpfull bunch. im a member of staff on there.
www.scottishmondeoforum.com