I'm a complete rookie and I did it myself.
I did the prep work (sanding) and I bought a compressor and paint and did it myself.
Your welcome to use my compressor if you want.
The primer, paint, materials etc for the outside will run you any where from $300 to $400 depending on the paint
But if I can do it you can do it too.

I dont thihnk it would be extremly dificult to accomplish myself. But I have no space at home to work on it and its fully rigged so its heavy as hell. Trying to move it around sourceing stands and keeping the trailer somewhere else during is just something I am not looking to do.

do it on the trailer. time and patiants is all you need, but a floor jack and some wood makes it real easy. do what you can then easy shift the boat and finish under bunks then back. i moved mine from my old trailer to the new one and it wasent to bad at all.

I also did mine in the back yard because I had the space, but doing it on the trailer is very possible. Worst case is that you put it on stands/bricks and have a buddy hold on to the trailer for a few days.
The worst part it sanding/getting off the bottom paint.
if you can at least get it preped then you have done the hard part
The rest is easy