I am going to buy a 78 nova in a few weeks and the guy im getting it from says he resored the whole thing but it has idle problems. I am tight on money and want to know how spendy that could get...

Idle problems are usually an open vacuum line or a bad carb gasket in most places, really cheap and easy to fix. If the engine is the straight 6, sometimes the carb sections get loose and suck in air, another cheap and easy fix.

Bob

Check for vacuum leaks. If it idles at all, grab a can of carb cleaner or and spray round the base of the carb, any vacuum line, intake manifold, etc. and listen for engine RPM change. If it smooths out, you found the leak. if it's not an internal carb problem, you could fix it with a new vac line, or a tighten the bolt fix.

This may be more of a long shot, but if the vaccuum leak checks don't work, you may want to check the valve adjustment. If he re-did the car himself, he may have over tightened one of the valves. If it gets stuck, the car wont' idle good, but may sound better if you rev it up. Adjusting the valves can be a pain, but it's cheap enough to do. it'll cost you a quart of oil and some new valve cover gaskets. Make sure you do it when the car is wamred up and running.