It depends a lot on your space and financial situation.
If you have space, you could set up a playpen with dig boxes of rice, tunnels, etc. This could keep him occupied and entertained. However, I don't know what your garage set-up is (maybe there are cars taking up the largest portion of the garage).
Is your roommate opposed to ferrets in general? You could consider getting one of those ferret knapsacks and carrying your fert around with you.
Depending on your financial situation, another ferret could keep Rikki company. You just have to be really careful (and honest with yourself) about whether you could afford another ferret, and if this would cause more roommate woes....
If you have your own room, you could set up a playpen in your room for Rikki to run around in, too.
Leanna
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"Dogs are followers, cats are self-absorbed, ferrets just are."
