Jorge, the car will need to be epoxy primed at some point. There is no benefit to waiting, and much downside to it..
My two cents: Painting a car is very expensive because there is much labor & materials involved. Even if the body is perfect the car needs to be cleaned & epoxy primed, inside, outside, underneath, etc.
Epoxy primer is very tough. Any needed body work can be done on top of the epoxy, sound deadened, undercoating, and so on. It is however, not friendly/easy to sand, so another “primer-surfacer” is sprayed on the exterior. It is easy to sand and is thick enough to hide small imperfections or scratches. The primer-surfacer is usually wet sanded with a rubber or foam block until the finish is dead flat. Then it is ready for color coat, unless you have areas of exposed metal or filler which require a sealer. The color coat most commonly used these days is base coat, and topped with a clear coat. The clear will usually require wet sanding and buffing to finish. So that is a lot of materials and labor... the last time I bought a half gallon of Plum Crazy base coat it was around $260. Clear coat is at least $100 a gallon, primer surfacer about $90, and epoxy around the same... unfortunately when I had fully finished wet sanding my Challenger’s primer and was ready for color my painter, Rod Alexander, suffered a hemorage and died... he was a young guy too. Anyway, another painter wanted $5000 just to spray the base/clear... not including materials; ridiculous for an afternoons work! I did it it my garage because I figured even if I screwed it up I would only be out about $500.
If you, or others reading this, are so inclined, it is an easy matter to prime the car yourself. You need a gallon of epoxy primer with hardener & reducer, mixing cups, a spray gun with about a 1.6 to 1.8 tip, a air compressor with a water filter, and a protective mask. It’s only primer, you cannot screw it up, and if you do, just let it dry, sand/remove it and re-shoot it. This can be done outdoors on a calm day because if/when a bug/ dirt lands on it it doesn’t matter because that spot can be easily addressed.. and the car is going to get a coat of primer surfacer anyway. Even a first timer can get good results if you follow the mixing directions, adjust the air pressure and spray gun, and practice on something (I use old parts or the sides of my trash cans), then start on hidden areas, insides of the doors, engine compartment, etc. This way you can get your car primed for a fraction of the cost. I will be happy to help anyone with any questions...