I'm not worried about vehicle theft with the Elio. With the low MSRP, cheap replacement parts available, etc and a lack of storage space for valuable items I don't think it'll be a target.
That said, I would worry about two things. My car's been egged four times in 5 years just for being a V6 coupe in V8 Iron country (Murica!), I also am in Detroit and people I knew when I worked in Detroit were victims of car-jackings, a friend of a friend was killed for his Escalade at a gas station in the ghetto. To solve this Problem I employ a 2 fold defense, manual transmission and a gun on my hip, give him your car, if he can take it he takes it but if he dosen't know what to do with the third pedal you have a weapon to defend yourself when he jumps out.