One way is to simply have a deck
locker. You can store paint
, gasoline, acetone, hydrochloric acid, and other nasty stuff in it, you can use waterproof plastic containers inside for additional protection. On my boat I have a number of "wet lockers" that drain over the side (actually, through the underwing). Some contain propane tanks
for the stove, others contain paint
and other vaporous products, another has lye, oxalic acid, hydrochloric acid and other nasty stuff, each in a waterproof container and secured against rolling and spilling.