I think you meant to say $500k is a decent down payment on a house, yes?
Basic 2-bedroom condos in the general vicinity of an East Bay BART stop seem to run $700-900k; SF proper with any hope of a short walk or bike ride to downtown, $1.3 - $2 million. There are $500k houses, but they're in Richmond.
I think to be $500k, a condo would have to be far from transit in the East Bay, but such places are mostly single family homes.