what is involved in repaiting?...is it straightforward or does it first involve stripping ect.?
What kind of paint is needed?
It all depends on what you want, how much time you have and how much $ you want to spend.
On a basic level, you could get some rattle can paint and just go to town (don't laugh, I've seen it done). It'll look more or less OK (if you avoid runs, drips and sags - easier said than done) until you use the boat. Then it will chip and wear badly. You'll see every surface defect. The boat will need painting again in a year.
Or you could take the high road and have the surface fully prepped, primed and sprayed with a 2-part polyurethane (Awlgrip or similar) and the boat will look better than it did when it came from the factory. The finish will be very durable. It will also be pretty pricey. Just the paint is $50 - $120 a quart
(depending on the color) and is really nasty stuff to work with (need a respirator - not just a mask - to spray).