I turned my phone back on on the way out, and within a couple of minutes was rung by the insurance company. Phone battery was nearly empty and I was chasing SC out into the car park so I said it wasn't convenient at that time.
Rang back in the evening to discover that my file handler has valued the car at £1,200 and already posted a cheque for £890 (which is after deducting the policy excess). I'll be disputing this, of course, but apparently I can cash the cheque without prejudice — or could, if I were not still Up North. I'm not quite sure what consequence this has on them wanting the hire car back.
Similar cars to mine on sale at Autotrader at the moment: £1,195 £1,279 £1,595 £1,695 £1,750 £2,499 £2,649 £2,695 £2,795. The more expensive ones have fewer miles, of course, but not by that much (mileage of my car was 83,670 and it was 02-reg).
(Link for £1,750 doesn't work but was copied directly off the search results; I guess either it'll come back or it's been sold)
What Car says I should expect to pay
On the previous post there were two recommendations for Corsas and two for Nissans (or anything Japanese). So far in the car hunt, we have:
Nissan Micra 1.5dCi Visia (2009, 29K miles, £5,495).
Peugeot 407 SE 2.0 HDI (2005, 58K miles, £5,399).
Vauxhall Corsa 1.3CDTi ecoFlex Active (2009, 11K miles, £7,990).
The Nissan looks good but is a basic model (lacks air conditioning, which I may well miss after having it in the Xsara). The 407 is very local, but probably too high-end for my needs. The Corsa is very very tempting (and comes with a Network Q warranty) but would require quite a bit of shuffling to get the cash together (and when I say cash, I really mean debt, since I have very little liquid cash to speak of).