We had our Keystone Outback (TT) repainted, but we let our dealership do it. It took about 2 weeks for them to do the work.
I think the biggest obstacles doing it yourself are (1) space, (2) time, (3) skill.
(1) You need a space to do the work. The camper will need to be under roof, dry, and in a somewhat controlled environment because....
(2) Paint needs time to dry between layers, and if you are working a full time job somewhere, your time is limited to after hours and week-ends. The camper needs to be protected from the elements while doing the work.
(3) If you are not skilled or do not have the right equipment, the finished product could end up being a disappointment. However, if you are skilled and have the proper equipment, the end result could be fabulous.
Time and space were the reason I let my dealer do it. I had no where to get the camper under roof to do the work.