The hardware store closes five minutes before you get there. A tenant's ability to see dirt and damage is much greater when the move in than when they move out. Your best tenants always get job transfers during the worst rental markets. Everything in your rentals will break 100 times faster than in your own home. The insurance inspector always shows up to take photos of the building as you are putting the evicted tenant's possessions on the curb.
Tenants always swear under oath that the window was broken when they moved in.
If it exists, your tenant will try to flush it down the toilet. If you have any questions about anything, ask your tenants. If it is pouring rain, you can be sure the windows are open at one or more at your units. Proper disposal of chewing gum is in the carpet. Here's how to change your monitor's resolution.