I just came across some development snapshots made in 2006 on the development of a database driven RV dealership.
Remember this is Drupal 4.74 CCK,Views,Contemplate, one custom module and some tweaking here and there (sometimes with a pipe wrench).
One of the major things was the theme, and because the designer (at that time) had little theming experience (I think not much designers had then, and this was a good one), I did the initial theming.
This setup also has a search that searched ranges of years, models, prices,etc
I'll have to reload this baby just to make a small video tour and show what was already possible with drupal 4.74
If you have any questions on this solution please contact me.