Most college kids aren't going to have a ton of stuff, so space is likely not going to be your issue. I think a good place to start would be calling a local storage unit company and asking them how much it would cost to rent their smallest unit. My guess is it will be like $30-$35 a month. Then I would tack on a small premium for the delivery service.

The bonus to operating as a pickup/drop off is that you don't have to spend as much to pretty up the property, since most customers will never see it.