A friend is visiting San Francisco soon with her infant and asked what to do about cabs/busses. DS is 6 months, so obviously has to be in a car seat still...how does that work? Do you just lug your seat with you and install it in every vehicle? How does the bus work?

She asked me because we visit NYC a lot, but during that infant stage we didn't really take public transit, so I don't have an answer for her! We live in Dallas which is VERY car dependent, so she's never used any form of public transit with her son.