[rdl]

It's a highly inefficient market. Very few people want to rent anything for >$5-10k/mo -- they'd usually (stupidly) prefer to "not throw money away on rent" and either pay $50k/mo for a mortgage on that property, or spend the same amount on a much cheaper house mortgage. (or, in more reasonable cases, pay $2-5k/mo on rent).

If you can keep your neighbors in check, I think $10k/mo mansions make awesome startup offices, too. That's what everyone does in the Middle East/Caribbean/etc., and works well enough in the Bay Area, too, until you hit a lot of employees.