[quote author="freedomCM" date=1245726706][quote author="Geotpf" date=1245644573][quote author="freedomCM" date=1245642598][quote author="usctrojanman29" date=1245616642]When the cost of renting is more than the cost of owning a home.</blockquote>
In a rational market.
(no maint, no tied-up dp, no insurance, no reserve fund for repairs, etc)</blockquote>
Maintenance, insurance, etc., are all "costs of owning a home".</blockquote>
Exactly my poing!!!
which is why renting should cost more than owning (as defined by PITI), no?</blockquote>
Not necessarily. Some people ONLY have those incidential costs (that is, they own the house free and clear). You can get the best rental deals from them, because they have no pressure to try to make a mortgage payment.
But then again, sometimes people only need a place to live for a temporary amount of time, or don't have the credit score, steady, provable income, or a downpayment to get a loan. Of course, during the bubble, one did not need a good credit score, steady, provable income, or a downpayment to get a loan.
Plus, if people are willing to buy property even if their costs are way above rental parity, demand is artificially high. There are some non-financial reasons to buy even if renting is cheaper (you can modify and decorate the house however you want to, no landlord looking over your shoulder, plus the "pride of ownership" signifying "you've made it").
In short, I don't think there's any magic reason whether or not purchasing a propetry should be above or below rental parity. I think "every market is different" in this case. For example, I imagine places with lots of people who only need short term housing (say, near colleges) buying would typically be below rental parity (because demand for rental units is artifically high due to all the college students). Places where lots of people have poor credit, low savings, or unsteady income would be the same (lots of people who can't qualify to get a mortgage, so more renters than normal).