I want to provide stuff on eBay or amazon. Any tips?
Answers:
Yes, don't over price.
Check out what that item or a similiar item have be selling for.
Do not over charge for postage or you will not seize repeat buyers.
Don't put on the market used things for the untested price... (you probably know that one already...)
Alright... pay attention around PayPal. I've hear that they sometimes impart out your personal information...
Beware of auction scam.