1. Always read all the information about the item you are bidding on. The other day I came across a bathing suit from a smoker's home. Not something I would want to buy.
2. Make sure the sellers' have a good reputation.
3. Price compare, how much would the item be new. Is it really worth it to get it used at this price?
4. See if a seller has other items you would like so you can combine shipping.
5. Sort by ending soonest. This way you don't spend 6 days thinking you are getting some great deal on an item only to be beaten out last minute by some other guy out of left field.
6. Always factor shipping into your purchases. Sure the bathing suit I was looking at for Cole was only $3, but with $6 shipping I would rather just buy new knowing I could return the item to the store.
7. Think about giving selling a go!
I was thrilled to get Cecily a cute Crazy 8s Easter Dress, Jacket, and matching hair clips shipped for $13. I missed out on a Little Mermaid DVD, but will keep trying my luck.