[akaKJB]

This will probably vary wildly from vehicle to vehicle. My '88.5 924 got up to 35/36mpg on a regular basis. My '88 944S is getting somewhere in the mid-teens, a situation I've been looking into since purchasing the car, so it's definitely a good question to ask EVERY seller and don't trust them if they're just pulling the spec numbers from the US automotive gas mileage database.

Having said that, if your only concern with a car after looking at it is the gas mileage, it's worth serious consideration!