Well I bought my Thule roofbars on ebay, putting in a bid of the max I was prepared to pay at the last second. Doubtless the ones I won there is somebody fuming about being outbid in a similar way to you – however before I bought mine I was also outbid several times by people just willing to pay more than me. Either up the amount you’re willing to pay, or be prepared to wait. Oh, and never bid before the last few seconds of an auction so that the people you’ve outbid don’t decide they’d maybe spend a bit more.
If somebody else is prepared to pay more than you, then why do you expect to win? Oh, and given your comments about somebody bidding £1 more than you, you do understand the proxy bidding and bid increment process on ebay?