Hi @Daniel530. Sounds like you plan to rent out your personal space when you are not using it, right? I think your plan to lock up your private important stuff is a good idea. There are no rules against limiting guest access. Guest curiousity or, worse, guest criminal intent is difficult to monitor when you are not there and strangers are in your personal space. Good luck!!!
Yes, of course you can. I am planning to do the same with my utility room and I'm even considering putting a lock on one of the closets to keep it private.