Questionhow much do you think it would cost to replace the rear window for a 97 sentra
AnswerHi April -
If this is just a replacement of the window glass, not the lift or regulator, it should not be too much.
Since your car is a popular model, I would check salvage yards, or used car part stores before getting a price on a new one.
I don't know where you live, but here in Hawaii, we have a place where they stock windows for popular models and provided they find a used one, can be replaced for under $100.
Hope this helps
aloha
calvin