Bay Area is a bubble, according to some experts. I honestly wouldn't know, but your 1.5 million can net you more leverage in other areas of California, or the US, if you are willing to put your money there.
I am not a PRO at all, so take what I say with a grain of salt, but I'd rather take proceeds from those sales, take it to a good neighborhood, good schools, good tenant, and good cash flow area, and start building my RE holdings there.
There's a lot to be said for those stable areas -- you won't see Bay Area appreciation but unless you were an investor 15 years ago in the Bay Area, I would imagine cash flow deals are impossible to find, even per your note "The property prices are very high and there will be barely any returns after expenses." There is money to be made SOMEWHERE but Bay Area may not be it.
The returns of the stock market are higher than normal. Folks are making 20% on their money, which is fantastic. But the stock market is not tremendously different than the real estate market -- sure, the ENTIRE stock market is up but not every sector is the right investment. RE is the same -- Bay Area isn't where I'd invest, but could you find a blue collar neighborhood nearby with stable tenants and cash flow? Sure, I bet you could, and that's where I'd probably start.
And finally, make sure you frame your decision-making to align with your short and long term goals. What is the POINT of your investment path and vehicles? I know what my goals are and it helps me to decide what to do with my money.