I agree with Rob, the 850 is not the best choice if you are on a budget.

I have owned plenty of Volvos, including two 850s, and they have all been great cars. That said, when one of the 850s has a problem, it is usually big money to fix. The turbos are more expensive, and avoid options like power seats and sunroofs.

I would get a 91-93 240, or a 940. Cheap, easy to work on, plenty of parts at the pick-n-pull, and much tougher than the 'white engine' Volvos. The key is to get one in good shape, and new enough to have an r134a AC system.

Regardless of what you decide on, make sure you have the car checked out prior to purchase, and then expect to spend a little money to get it right.

Good luck.