I don't think you can really assign a value to it. Most cars - even ITRs - are plentiful enough that you know what similar cars (similar year, mileage, and condition) are selling for. Unfortunately, this one is a one-of-a-kind - not in a good sense - and so you don't have a bunch of other beat-up, modded, non-operational '97 ITRs with 67K on them to compare it to.

Unless you have a lot of experience in body shop work, I wouldn't buy it...