A few years back we had a guy around here that bought a unit with many trash bags full of clothes in them. He was more interested in the other items in the unit and didn't pay much attention to the bags of clothes. So fast forward, he's at the dump throwing the bags of clothes out of the back of his truck when one of them rips open. Nestled between the various items of clothes were rolls of genuine US legal tender $1, $5, $10, and $20 bills. Needless to say he dove into the pile of bags and recovered a couple of them. The others were to far down to retrieve. Out of the few bags he saved he found close to $2K in money. He has no idea how much more was lost in the bags he couldn't retrieve.
Another guy more recently bought a unit with a pile of books in it, and nothing else. No one wanted it because books don't bring in much and they're a lot of weight to haul out of there. Anyway, this guy says 5 bucks and gets it. It turns out that in every book in there each 100 increment page (100, 200, 300, etc.) had a $100 bill in it. All told I think he said he pulled over $3K in cash out of the books.
So you see, if a tenant asks you not to go through the bags of clothes, it's the first thing you should be doing.