In reply to FesteringSore:
Not a hard rule, but as a buyer I'm very suspicious of second chance offers and would take time to consider.
As a seller, the few times I've done this, I usually "explain" why it's a second chance offer - buyer ignored paying, wanted to withdraw and I accepted, etc,. It's all about trust both ways I personally think. I've have sometimes just relisted as this was the easiest and quickest. That also tests out if in your case £120 is the price or £90 is more realistic. Many buyers get carried away in the final stages of an auction, and this may apply to the second chance person who now feels to them £90 is the right price.
Edit: if you feel it's a p... take, if it were me I would just go straight to relist. Not worth the hassle of any communication other than curtesy reply saying thanks, but sorry £90 is too low, I'm going to relist.
Post edited at 12:13