@Jon B. This one is a little out-of-the-box but growing up my family had a few SFR rentals. What always surprised me (then) is how badly the tenants would treat the property. How did the hole end up in the wall? Why is the grass 12 inches long? What's this weird stuff stuck to the stove? Is it even food? It was a night-and-day difference from the way that I grew up. What I learned from that (and what I know now) is to hope that they take care of the property the way that I would but plan (and BUDGET!) for tenants not to. Overestimate maintenance costs, cap-ex holdbacks, needed reserves, etc. and you won't end up having a heart attack when one of those challenging tenants passes your screening process.