largely depends on the vehicle, condition/type of paint on it, what bodywork needs to be done. how its prepped, what materials they are going to put into the job. what you reasonably expect this car to look like when its finished. how much effort your willing to make in finding someone willing/competent to do this. do you want a gaurentee? interior maybe be a little more tricky depending on what needs to be done. seats door panels might have reproduction pieces that can be purchased. dash pad/arm rests might have to be sent to speciality shops. you can get a carpet kit and a shop can redo the headliner.. i'd say about $500.00 per lineal foot of car would be a good starting point for budget purposes.
too broad of a question. you really need to ask a shop. look around. ive had body work done on cars that was estimated from $400-$1500. it all depends where you go and what needs done. shop around. good luck
in addition to the previous response, it also depends on the quality of work. something done at MAACO could be as little as a few hundred. but if you want a good paint job, which i recomend, it can be a few thousand. for interior, it really, really, really depends on what you want done, it could range from minor things being again, a few hundred or major to a few thousand.
i had Maaco paint my '76 olds. cutlass supreme brougham, they also removed that vinyl clad/crome tipped body side molding, filled the holes. it needed some rust repair behind the rear tire and front(typical on these cars), i provided some "fresh" sheet metal(by fresh i mean i sawzalled it out of a '77), for them to do the repairs. also the trunk hinge was sprung. after they painted it/door jambs/trunk lid/wheels it looked great, cost 3 grand. for the money spent it was worth it, the next lowest estimate was 9 grand and i'm not sure it woulda turned out a whole lot better. i mean for crying out loud its a 76 cutlass, they made like 1/2 million of these things, how can a guy justify that kind of money for paint, they also installed door hinge/weatherstripping too.
depend on ur car and model year. check with a local dealer.
Depends on the shop rates, cost of paint, labor. Not 100% sure what any of the shop rates are in my area since I just moved out here, but paint could run you $50 to $150 easy (depending on color, and brand.. better brand, more expensive) PPG is decent, not priced extremely high but they do have a nice selection of colors to choose from. Buying the paint yourself, and then taking it to the shop would save you money and time for you / shop. Again it depends on the shop rates... I used to charge 80 an hour... but if they had the paints and supplies already in the vehicle, I would charge a little less cause it saves me time.