[Echo-chan713]

what kind of items, if it's non common item there are price guide for you to estimate the price range for each item so you rip them off nor the other way around, you can haggle the prices if you think the buyer's price is a little too low for you, we won't bite at all

for commons you can sell it back to the shop but it's half the price so you could go 20-30% discount from the original price on the commons