$500 is realistic if the car has worn seats, delaminated door panels, a sagging headliner, shrinking door seals, worn suspension, a Nikasil and a ton of deferred maintenance.
If it's in reasonable shape, I'd say it will fetch a grand. Possibly two grand if it's in great to pristine shape and only needs a transmission.
Alex, if you think $500 is getting raped on a brake job --
On an E39 M5, the car that everyone on this board seems to want to own, ONE front, directional rotor, retails for $288.
I'll never forget picking up some parts at the dealer one day about a year ago and witnessing some poor sucker who just found out that his E39 M5 needed a brake job AND had a locked front caliper.