You can also do a search of completed eBay auctions for similar equipment to see what people have paid in the past. Read the descriptions carefully. Details about the condition can help you decide how much to bid. If you have a question or are unclear about something in the description,you may want to e-mail the seller for more information before placing your bid, especially for more expensive computer equipment. Ask specific questions.
Most sellers are happy to answer.
You can set your bid for the maximum you are willing to spend. If someone bids against you, eBay automatically raises your bid so that you remain the high bidder until the bid amount reaches your limit. If there is a lot of feedback, at least glance at the recent responses and any negative feedback to see if there are any comments of concern or issues you would want to clarify with the seller. The seller will then contact the high bidder to arrange for payment and shipping of the computer equipment. There are escrow services available for a small fee if the buyer would like to see their computer and accept it before payment is released.