make sure close if not all are 100% LEGO.
You should do real good on those. First they were free so all will be profit. Do not know if you do a lot of LEGOs but the first thing I would do and I do this no matter were I get them from, wash in light bleach water some can be real nasty. Then I sort brick from minifigs and accessories. I spend a lot of time make sure close if not all are 100% LEGO. First thing someone looking at buying them is seeing how many are not LEGO. Any way I may be telling what to already know.