One of the best pieces of advice that I can offer to anyone bidding on anything on eBay, and especially if they are buying PC parts is this:

Do Your Homework before bidding!  I have seen items go for more here than I can buy them retail.  Before I place a bid, I make sure that I know exactly what I am bidding on, how much I can buy it elsewhere, and whether or not I have the funds available to pay for it within 1 hour after the winning bid.  This last part is extremely important.  If you are bidding and are expecting to win, but do not have the cash readily available, then you are wasting everyone's time.  Here, the old saying that time is money, is true.  Sellers have to pay to list their items, even if they are not sold.  As well, they pay again to relist the item if they sell it, and do not get paid.  That results in a lower profit margin, and most sellers don't have the wiggle room, so they get discouraged if they have to keep paying  to sell, then not sell due to the bidder not paying.  Try doing that at Wal-Mart, it just won't happen there, and it should not happen here either.

Another great piece of advice that goes hand in hand with the "Know what you are buying":  If you are unsure of the item's condition, or if it is not marked the way that you feel it should be, contact the seller!  I have contacted sellers just to let them know what it is they are selling if they claim not to know.  That comes from researching the item outside of eBay.  Let's say that someone has a motherboard that has a socket 370 socket, and someone wants to know how big of a chip it can hold, or how much RAM it supports.  I look up that information, and send it to them.  This helps them sell the item faster, and it helps them better understand that buyers need to know as much about a product as possible, before they are willing to take a chance on it.  This is the same advice I give to sellers.  Do Your Homework First!

My last piece of advice is this:  Be sure you know the value of the item you are bidding on, and be sure that the shipping and handling is not going to make you pay more than the item is worth.  A lot of my winning bids have come from the willingness to bid a dollar, then base my cost on the shipping.  Monitors are great for inflated shipping, so everyone can buy one for a dollar, then put the 40 to 50 dollar s&h into the calculation.  Some sellers will inflate the cost of shipping so that even if they do not get a bid that they want, they can still make money on the sale.  Though I would not recommend this practice it happens alot, and is something to pay strict attention to. 

I hope that this information will help atleast one person who takes the time to read it, and pay attention to it.  I have been an active eBay buyer for a long time, and I have had to learn the ropes from the ground up.  If you are a seller, I highly recommend that you check with your local shipper for pricing, as the shipping calculator on eBay can leave you upset and scratching your head wondering why you lost money on a sale that you thought went well.

Respectfully,
   David Moffitt / Owner
    CortlandPC Services