I get about four weeks. I'm leaving the day after finals end and coming back a week early.
Ouch, no fun. We almost always can go to the user, or have him bring a laptop to us, so no working blind, thankfully. And, if they're not willing to work with you, tough luck, they can have a broken computer.
We provide limited tech support for student machines in the residence halls...if it's something hardware we tell 'em no dice, but for other stuff we at least attempt to help, especially if it's network related. But we don't do house calls unless there's a busted jack or something like that. That's something we have trouble getting across sometimes. They ARE allowed to bring machines down here if it's something network related that they're having problems with...which also ends up meaning spyware and malware, since we deal with a lot of students with browser hijackers.
At least this year my boss finally said we don't work on a machine unless it's up to date on antivirus software. That's saving us major headaches, especially since we don't get many "repeat offenders". It DOES mean than most students with old machines that haven't done anything to maintain them get upset because there's not much we can do for them.