As long as you only go for a satin, or eggshell finish there shouldnt be an issue, problems can arise when too much matting agent is used, and your paint finish ends up looking like a school blackboard, and will eventually turn grey!
There are 2 ways to paint your car, either use black basecoat, then lacquer, only the lacquer will have matting agent added to it, typically, 2parts lacquer, 1part hardener, 1part matting agent 1part thinner (this is the best, but most expensive way. but your car would look awesome!)
Or, have black topcoat mixed, and have the matting agent added for your desired finish..
Best result would come from 2 people painting your car at he same time, this would give a more even finish, and less likely to get "stripes" from over application in certain areas..
Upkeep of the paintwork is easy, just dont wash it in the sun, and get it dry asap! you can even wax the car, as long as the wax has no cutting, or abrasive qualities, , plenty of products out there
Tom