You can check actual UK property sale prices 2000-2004 on http://www.ourproperty.co.uk
I just looked at a few that I used to have:
Higham, Rochester. I paid £10,000 in 1977, it sold Dec 2000 for £127,500, and again June 2002 for £157,500 ( I sold for about £30k in about 1980)
Strood...