potential used car purchase

i m in the process of considering a 1997 Mitshibutshu Galant....it's a great car that seems to have all systems go, the final thing is to test drive and let my mechanic scutinize the vehicle......the query that i would like to present is this......the car has a slight but potentially hazardous nick in the front windshield, one that most certainly has to be fixed, either entirely(the most likely scenario) or partial ( i doubt that one)..AND.. the passenger side power controls do not work (the window does not come down.. this i would imagine is a simple fix.....fuse or switch or otherwise electrical in nature).........i would like to know if i should have the dealer fix the problem OR take up his offer of having the price reduced (by$400) and have it fixed myself OR wait until my mechanic sees it and make my decision thereof?....incidentially, the car checks out good via carfax (1 owner, no accidents, etc, etc )........please advise......THANK YOU!!