If you are going to hire a contractor (professional painter) give a room by room punch list of the fixing of holes small or big, have it identified for the painter to tell you if you need a drywall finisher or if he does this type of work good. Wall repairs can be 3-5 steps to do repairs ( one per day for good drying of patching material and a good sanding) this is what gives you a good paint job only using high quality paint.
If a quote seems high, ask the contractor what is increasing the price point. Perhaps it's something that can be negotiated, or maybe this business is just overpricing their services. On the other hand, be skeptical of any price points that seem unfathomably low. There could be a reason their prices are below the industry norm - perhaps their quality standards are uncommonly low, too.