Read this whole thread, and visit https://www.dipyourcar.com/home.php?...Fc2d4Aod_nsAIQ
Watch some videos on you tube and decide if you can do it yourself. Doing your roof now, and the rest of the car later should be fine. If it don't match well enough, peel the roof and redo. Perhaps your high school has a vocational school area with a body shop. Perhaps if you present this properly, as an up and coming way to temporarily paint cars, yours can be the test subject.
I used 2.5 gallons camo green and a Wagner Power painter to do mine. all the black was with spray can.
Post some pics as you go, and good luck.