HHHhhhhmmm, seems a bit high. I paid £9k for mine back in 2010 with nearly 70k miles on it. I never had any problems with it just did servicing and replaced consumables, plugs, pads, tyres, wipers, aux. belts. Bodywork was good having had the front bumper resprayed and dents in the doors pulled. Eventually had to accept a low trade-in price for it of £5k with 97k miles on it when the market for Zeds was depressed in 2013. Then, similar cars were fetching £6-7k.
GLWS though. Maybe the market is right for you.