I've painted a few cars in the garage and it's a PITA. What you'd need to do is go to your fav home store, and get pastic that will cover all of the walls. And the floor. And the outside of the garage doors. Plenty of ventilation too. Then know it'll stay make it's way onto stuff.

Not sure if you've had much experience with automotive spray painting, but I've found it to be much harder than it looks. The temps and humidity need to match the activator. My last paint job I must have gotten that wrong as it left a residue on the car. Needed to spend a lot of time buffing it. In the end it came out pretty good.

If you decide to paint it yourself, based on what you're saying I think using fleet paint is a good option. I've used it on my cars three times now. It won't look great for 15 years, but I've always figured that a racecar would need to be painted every few years anyways. It's also inexpensive. http://www.levineautoparts.com/autopaint.html

What does Maaco charge to paint a car? I don't see prices on their website.