I've been trying to sell my car, and have just done so, but I kind of fucked up. I put it on ebay with a reserve of £2500, thinking it'd go for a bit more than that, just to get things going, but it's gone for £2575. I was hoping for at least £2700.

The auction ended while I was at work, and I got in yesterday evening to find it had ended. I then also saw my phone, and I'd got a text from a guy who had come to see the car - he lives in the next village, he's a local down the pub I work at so he's not really a stranger, wanted it for his teenage son, and has offered to better the ebay price by £300.

So I messaged the buyer saying that someone came and offered more, really sorry, would have cancelled sooner if I'd known but I was at work all day, etc. etc. - he's replied saying he's furious, he had 'promised this vehicle to [his] fiance]', he wants me to sort this out or he's going to report me to ebay for unethical behaviour and leave bad feedback.

I could cope with bad feedback but I've been reading around and it looks like pulling out of a sale, especially one as big as a car, is a big big no-no on ebay and can sometimes result in being banned from the site, or at least being banned from selling anything else.
Shit. I don't know what to do.