I actually start with a base price of $250,000 in 2000 for above home, that leads to slightly under $400,000 in 2008 at 6% annual growth rate.

How many people do you know that have gotten 6% raises every year since 2000? Incomes have been flat or declining for the vast majority of folks (like those who buy San Marcos homes). I would wager that actual wage growth is more like 3% per year since then once you exclude all of those involved in the great housing scam of the early 2000s. So those $250K houses in 2000 should be worth somewhere around $316K today. Of course it overshot way way big on the way up so it is likely to undershoot on the way down IMO.