Can you list the reasons you think houses prices went up so high during the housing bubble?

I can think of: 1) the govt manipulating interest rates and keeping them low for all those years after 9/11. 2) The advent of all those new loan programs that made it so easy for people to buy houses using those teaser rates adjustables mortgages that erstwhile they might have found unaffordable. 3) The subprime mortgages with no income verification no est verification, no money down needed etc.. All 3 of those factors created and increased demand for housing and speculation from investors looking to cash in on the housing price hikes. Now of course, the question is..with the credit crunch and lenders being stingy on making loans and rates rising, how low will the housing bust go?