if your having concerns now, better to voice them before you get further into this project. go talk to the manager and explain to him why this is making you uncomfortable. if he handles it properly he will explain the situation more clearly to you, and maybe even offer you some sort of deal/discount for the unprofessional way it has been handled. definitely bring up the smoking issue. that is disrespectful and they are risking damaging your car and its value. if the manager does not put you at ease, its time to take it somewhere else, and i for one would refuse to pay even that full $300 if you walk out of there without any sort of fix.
