boat builders, fibre glass supplies they also stock other good supplies.
go to a medium size boat store and ask questions to price a job, don't make shit up, just get prices
plan to do a glassing job, draw a box for storing something or a funny shape fountain/rock feature whatever, draw it out on paper then go costing it up.
ask about gel coat, glass weights, sanding, bogging, painting, cleaning ask heaps of questions and take info and prices off the now bored sales assistant.
its a dry run, you learn more about what they say is good to get.
take your notes and go to boat builder (with crispy cash kaching) and get the bits you "still need to get" from them.
when you buy industrial grade by the drum, its about $$$ and often there acetone, mek, dcm is a lot cleaner because larger more focussed suppliers move big units and arn't in the business of charging heaps for old shitty incorrectly (but fancy) packaged retail sized red herrings.
remember you know nothing, so why would you specifically ask for a certain chemical. just ask away till you strike some friendly bugger you tells you what you need.
nb: they buy the drums, you buy a couple of litres.
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