I actually looked up the Lemon Law when the battery failed to fix the initial problem. There are no protections for used car buyers outside of the court of public opinion, unless the car is specifically sold with a warranty.
Walking the five miles home will be a necessity, I'm afraid, as I get done around 3am and the first bus out of the terminal is 5:45 (last bus leaves at 9:45). Getting done early isn't an option, as I drive a dedicated cargo route and am about 100 miles from the office at the time I'd have to catch the bus.
Thugs and thieves, at least, I don't need to worry about, due to trekking through a mostly semi-rural area and the fact that they're usually not prowling that late.