The issue you will have is getting parts. Since the car was not popular, there are not many companies making reproduction parts for it. OEM parts are scarce too. Luckily, the drivetrain was used on many Mopar products in the late 60s and early 70s, so engine and tranny parts will not be the issue. It will be the little things like trim pieces, dashpads, things like that.

As is always true with Mopar products, all parts will be more costly than a GM or Ford product. Not crazy, but just more. There is not as big a following for those parts, and people who have them charge accordingly.

Look for rust. Rust plagued many cars of that era. the common places to look are in the trunk where the floor pan meets the wheel wells and cabin divider. Lift the carpets and inspect the floorboards. If the car has a vinyl top, look for bubbles under the vinyl, especially around the rear window.

After all that, is $4500 too much? I dont know. I would need to see the car and find out what it was equipped with. It might be a good buy, it might be too much. Without seeing it, I am thinking $3500-400 max.

Here is a price guide – look to see which model you have, and put an honest estimate of its condition to get a fair price

http://www.imperialclub.com/Yr/1968/Prices.htm

How to put a number on your car
http://www.imperialclub.com/Yr/Condition.htm

If it was used during winter weather, it is definitely over-priced.

I suspect the car is only worth 2500-3500, but I haven’t seen it, so who knows. My main point is, get it thoroughly checked out. If you’re looking at hundreds of dollars of fixes, you should really get your co-worker to knock down the price.