I do, but still part time. I have a few jobs booked in for this year, but have already had to re-schedule some due to unforseen circumstances (on the customers part). I have now got access to a proper detailing studio that I can rent on a job by job basis, which is handy, and it's only around the corner to me.
To do a car this small, from top to bottom, I'd estimate at over 30hrs work on the exterior alone. It took me 3 hours just to do that upper part of the door!! Price wise, you're looking at anything from £750-£900. I do a 2 stage machine polishing process alone though, with no wet sanding, for that you're looking at around £450ish, which on a Punto would represent better value for money - unless it was a show car. That would remove all swirls / spider webs and about 90% of all other marks. The wet sanding eliminates the last 10%, then obviously you can go further again and flatten the orange peel to get a mirror finish.