@Matt K. that's always the risk. If you are purely in the game for appreciation, there is always that risk. If you can hold onto the property and the rents are covering your mortgage or breaking even, then I would assume one would just hold through the the downturn.
I'll share specifically two of my properties I bought in 2012 because the others are with partners and not for me to share.
Single Family in Pittsburg bought in 2012 for 124,000 cash. Spent 25k in renovations and repair since then, now appraised at 389k+, but had offers in the mid 400s but I decided to keep it cause I got a consistent long term tenant that pays currently 2200 and covers all the utilities.
5 unit townhouse in San Lorenzo bought in 2012 for 564k and some change. Was completely run down and spent over 200k since then. This was bought through a family friend who had financial troubles and I helped him out. Each unit now rents for 3,125 per month, that's over 15k per month in gross, expenses equal to about 5k per month, plus or minus depending on maintenance. This property is now valued at over 2.6m.
By all means, East Bay has great rental potential if bought back then, and many still find great deals, but I personally find it harder and harder to find deals. I may find one or two good ones a year. Some call it luck that I acquired these properties, but as others mentioned, opportunity presents itself to those that are prepared and I was prepared with cash back in 2012 to make these acquisitions.