There is quite a range of paints/coatings that one can use on the inside (presuming the fiberglass furniture) and the outside, with various plusses and minusses, costs, and application methods. Not to sound un-helpful, but we have had a number of threads in which people have taken the time to type at length about the options - I think if you search the archives here you will find some really good, specific information.
In a nutshell:
Prep is paramount, no matter what you do. Painting
is just this little step you do at the end of the prepping process
For coatings, you have everything from a one-part alkyd-based paint brushed or rolled on all the way up to a two-part LPU sprayed on. Results and longevity of the coating and shine vary according to how good the prep is, and how good the coating is. Two-part coatings will generally keep their shine quite a bit longer (20 years is not unheard of).
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