What's my car worth?

[Redmax]

Hate to start a thread like this but I didn't find anything too comparable for sale and I'm doing some business case preparation to get some changes through the financial approval committee (i.e. Mrs Redmax)

59 reg (last of the 09 model years)
Exige S, 220 BHP
Chrome Orange
16k miles
Touring pack (I think - it's got air con, electric windows, ipod connectivity, that sort of thing anyway)
Good condition - Ventureshield, never tracked, no scuffs on the alloys
2bular exhaust
One owner from new

What range might I expect as a trade-in or private sale?

Cheers