What about if you calculate the cost of everything you ever had fitted to one particular frame?
My Dave Yates has had over £1K of forks since I bought it in 93. There's easily been £3Ks worth of parts on it over the years, not including the frame itself. Luckily I've been trade for most of that time so the bill has been considerably less.
Would be lucky to get £600 for it should I sell it on....
Certainly not ashamed of it though as most stuff was changed due to wear and tear...