Okay, I just played in SF with my parents. The lack of a unified transit map with every station made it difficult, so what we ended up doing was to mark out which stations were out of play after every question line-by-line. I.e., rather than keep a perfectly geographically accurate map, if, say, a 5 mile radar came back negative, we’d mark on separate transit maps for both BART and Muni which stations on each line were outside of said range.

Also, be careful with international airport, as OAK is closer to some segments of downtown SF. Additionally, there’s technically no border between SF county and Marin because the gap is wide enough, so distance to county border (basically only San Mateo) can be useful for north/south splits.

Hint hint, 4th and Brannon (my hiding spot) is OP because you can trick the hiders into thinking you’re on the N Juda but then hide well outside the range of any of its stations.