I painted my first car last fall, it turned out much better than I expected. All said an done it took about 80 hours to complete and around $800 for the gun, paint and misc. supplies (sandpaper). It was a Corvair Convertable so it's about the same size as a Z. The car had old laquer paint so I stripped it to bare metal to avoid adheasion problems. Here's a few things I learned;
1. Dust control
2. Dust control
3. Bug control
Almost all the visable flaws I have came from dust or bugs.I swept my garage twice then put up plastic sheeting on all surfaces and taped and stapled all joints then vacuumed the floor yet I still came up with some dust in my finished product. It must have come from the car itself or from my clothes (I didn't wear a tyvac suit). After my second clear coat I noticed a giant mosquito stuck to my hood! I painted at night and the lights in my garage drew bugs in.
I had a box fan with a furnace filter upstream set up to blow air into my paint booth. It was not enough. While I was clear coating a dense mist almost obscured my vision. Next time I will rent a ventalator or two like they use to dry wet carpet, they move a lot of air.
Watch a lot of utube videos and practice on whatever you can. I had an old washing machine that is now a nice silver/blue semi metallic.
6. Don't do a metallic for your first paint job.
The counter guy chuckled at me when I told him my paint code and it was my first time. It turned out well though, a little 'tiger stripe' on the hood where my coverage wasn't perfect ( I'm the only one that sees it). Refer back to #5.
7. No paint can cover poor prep.
Prep is where 70 of the 80 hours went.
8. Beer will NOT prevent paint job issues, only ease the pain once it's done
I will definely paint more cars, the diy pride is really worth the work. I crused the local Maaco holding area and their work looked flat and lifeless where mine shines.