I'd get myself along to my local Audi dealers and get them to:
1. Give you the latest Glass' guide price for your car with 20K miles on.
2. Ask Audi if theycould vouch for the condition of your vehicle (I'm assuming they serviced it).
Below is the glass's guide for my car
Audi S4 2.7 quattro Saloon 4d 2671cc
Valuation date: 27.10.2003
Year & plate: 1999 T
Mileage: 25,000 miles
Trade in - excellent: £ 13,350.00
Trade in - average: £ 11,800.00
Trade in - below average: £ 10,200.00
Retail price: £ 16,500.00
Should I expect them to offer the trade in value or the retail?...This is far off the Parkers guide quote which is more what I am hoping for
I am hoping they would offer in the region of £17k!!
Rgds...jem