Property tax is pegged at about 1.5% of assessed value, adjusted for inflation, which is reset unpon ownership transfer. Outside of "tight" housing areas, there are plenty of houses under $800K in the Bay Area, and the state in general. Top tax bracket is, I think, 11% or so, and sales tax is 8.75%.
"San Francisco area" is a bit nebulous, since that potentially encompasses everything from Mill Valley/Sausalito down to Silicon Valley, and eastward across the Bay. There are new houses that sell for about $1M for ~2500 sqft, but there are other new ones that sell for substantially less, as well as older ones that sell for even less.
One thing you should be aware of is that most of the coastal parts of the Bay Area are notorious for fog and overcast, so if you need lots of sunlight, you'll need to choose your home site carefully. Pacifica, Daly City, and Outer Sunset in San Francisco are all areas where overcast and fog prevail, even on days where 5 or 10 miles inland it's 80°F.
TTFN
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