if you have prep and paint skills and equipment and a wind proof location (with the correct filters for many modern paints) ... it is very possible
otherwise your results may not be so great
i have hulls that were painted grey (professionally)
looks great but ....
every scratch shows the white under it - extra noticeable
my grey hulls can get very hot in the sun 20% hotter than a white boat
i have awgrip on my spars and imron over all fiberglass
it is a ridiculous amount of time and energy (and money) to get professional results
but doable if you have the time energy skills location and equipment (and money)
also 2 part pain is crazy toxin to human and environment so proper gear (full protection and enclosed paint both with filtration) is really important
depending on your current boat's condition - you may be better off with a thorough cleaning and polishing. gelcoat can clean up pretty well
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