You have received good advice so far and some things mentioned I never thought of. One area I think of is safety. I would put a sign up that states you are not responsible for accidents and try keeping rummage shoppers from entering the garage area to eliminate potential accidents. Another thing is I have had people ask before if they can use the restroom. I would tell them to go to a local store or gas station since you do not know who you are letting in your home. It might be someone trustworthy but then again it could be someone checking for items inside your home to see if there is anything of value in there. I am just a cautious person and watch out for my safety as well as my family's safety. I hope this helps you and possibly others.