I have a colleague that asked me for a ride home once because he had to get home in a hurry, so I gave him a lift. Now yesterday he asked for a ride home again, and while I did give him a lift, I decided it's the last time.
(Generally, I don't like driving people around, and on top of that this guy is a bit disrespectful in that he does things like slamming the door, getting fingerprints on the windows, stepping all over the frame while getting in/out, etc.)
So, given that we work together, what's the best way to tell him no, next time he asks? I'm not afraid of saying no; in fact if anything I have a tendency to err on the side of being too blunt.
However, given that we work together, I'd like to decline his request in a tactful manner, so is there a better response than my natural reaction of telling him to "walk, get a taxi, or buy your own car" ?