I can't click on them because they're always covered by the walls of the car

You can run the MC command of your choice through City Hall instead. Use either MC > Sim > Advanced > Edit in CAS or MC > Sim > Stylist, X out the filter, then pick the sim from the list.

If you don't know the sim's name, try running MC > Sim > Status > Career for any sim whose name you don't recognize. Filtering the list for homeless sims first would cut down the list.