HA! 3k for a black spray job, that's cheap shit if they're gonna do the whole car.
You'll get it for under 2k if you prep the WHOLE car yourself and if you smooth all the inperfections in the body, cause they will all show up 4 times worse than they look on whatever colour you have now. But even then, probably under 1500. Depending on who you go to, but the most time consuming and money consuming bit is smoothing inperfections and prepping the car, so yeah, just warning you, prep all fo what you can and it'll make it alot quicker to get done and it'll be a better paint finish.