The last thing you might want to look at is the assessors websites for your area. The sites generally have a search feature to look up information about any and all properties in the given area. IDK how the SF area is; around here we have an assessors site for the main town, and then any homes listed outside of that town are listed on the county assessors sites.
What I liked to look for on this site was a few things:
1. Sometimes with a new listing there is no picture on the MLS yet. The assessors sites around here generally give you pictures (although they may be a 2-6 years old they give you an idea of what type of home it is).
2. They list the history of the home. Have there been any permits for new roofs, additions, windows, etc? We looked at one home with a beautiful addition that was NOT listed on teh assessors page. I called the assessors office, and they said property taxes should be much higher on that home, and also the work was probably not done by any liscensed contractor, and they wouldnt have had a permit to do it. I was glad to have that information, and we decided against that house.
3. Sale information. IDK what the turnover rate is in SF area, but around here people tend to stay in one place for awhile. I tended to be more critical of a home when it had changed owners 3 times in 5 years. The house we bought had been owned by the same person for 18 years. I tended to think if the home had any major issues, it would have been sold before then.
4. Other info. As you have probably noticed, some MLS listings are extremely informative, others are not. Our assessors sites list things like central air conditioning, sq footage of the garage if there is one, sizes of porches, decks, etc. Type of heat. Construction material (brick, asbestos shingles, frame construction, masonry, etc.)
Hope this helps you