I've done complete cars twice (in garage). Here are a few of the most important points:

You will never get it completely 'paint booth clean' so plan on cutting and buffing the paint. This is not a bad thing, as it has the advantages of: Removing dust nib's, correcting runs/sags if any, and correcting orange peal. My first car I lived with the dust nibs (didn't cut/buff) but in hindsight I should have. My second job is truly show quality. Go into the project with the understanding that you will cutt & buff the car and your results will be better.
Lay down enough paint (either the single stage or the clear if BC) to allow for this!

Do NOT put plastic on the floor!!!! Guess what happens when all that sticky overspray lands on plastic and you try to walk on it! Use heavy paper, and tape it down well.

You will need ventilation, you want to move most of the airborn paint out of the area otherwise it lands on the car between coats.

You need personal protection--you know that. Carbon respirator canistors (even though not OSHA rated for isocyanates) are fine for these tasks since we don't do this often (a pro would be wise to use fresh air hoods)