A lot of San Francisco listings don’t display property square footage so that your first impression of the home isn’t the $ / square foot cost. I think there are cases where this can make sense (e.g. homes with auction value) but by and large I think you’re better off sharing the datapoint even if your asking price is high on a $ / square foot basis.
One thing that I recently discovered is that you can often get property square footage even if the listing doesn’t show it. As an example, I looked at 1178 Greenwich Street about a month ago and estimated it to be 1200 square feet because Redfin didn’t show the square footage. Well, it turns out that 1) Zillow does show the square footage for this house and 2) there are two other ways I could have gotten it. First, Redfin has a public facts section that reveals the square footage to be 1275. You can search on a Redfin listing for “Finished Sq. Ft” to jump to this section, if it exists. And if that doesn’t work you can search the parcel through the SF Assessor-Recorder Property Information Map and you will often find this datapoint as the Building Area. In order to search the Property Information Map it’s easiest to copy/paste the parcel (abbreviated as APN) from the Redfin listing. In the case of 1178 Greenwich street, the parcel is 0071/076.
If you’re looking at a Tenancy in Common (TIC), you’re probably out of luck unless the listing tells you or you ask the agent, because the subdivisions aren’t recorded/recognized as separate parcels with the county (aka the TIC downside….shared land ownership and co-mingled finances).
And a reminder – whether you are given square footage or have to do some hunting for it, I’m a big proponent of scaling the square footage by some sort of usable square footage score so that you look at your cost in terms of effective space rather than nominal space.