business and resale cert

Hi
i have a sole prop business registered that i have not operated in some years. It dealt with making and repairing leather products.

I have a separate LLC that deals with riding lessons. (not required to have tax cert)

I now want to get back into making leather goods and now need a resale cert

question is... which is easier and makes more sense?

use the llc? or the sole prop?

if I use the sole prop I will have to file 2 schedule Cs at tax time