We don't own any rental property, but we rented for a lot of years. I was friends with one of the property managers we were renting from, and after seeing what the "average renter" does to a place, there's no way I would ever consider being a landlord.
We were a landlord's dream ... stayed long term (usually at least 2 years) and left the place in as good as, or better than, the condition it was in when we took up residence. But your "average renter"? Because the property isn't theirs, they couldn't care less about keeping it up ... hey, it's somebody elses problem, right? My friend showed me one unit after a couple of girls moved out. Holes in doors, broken mirrors, torn carpeting, gouged linoleum, trash all over the place ... it was really bad. If I remember correctly, it cost the owner about $3000 to fix all the damage and clean it up.
The last house we rented was trashed ... the owner lived out of state and had a "friend" living there prior to us who was supposed to fix a few things. Not only did he NOT fix anything, he pretty much messed everything else up. The owner couldn't afford to fix it up (why he even owned rental property without the ability to keep it up is beyond me) and we decided to take it anyway because my friend (the property manager ... she had just signed up to take this property too) negotiated a killer deal for us on the rent. So we worked a deal with the owner ... we'd pick one project a month and fixed the place up for him, taking the cost of the materials off the rent.
Bottom line ... there is no way you can be picky enough about your renters. You may get lucky an find a pearl amongst the swine, but you can get bit bad even if a renter seems like a peach. If you can't afford to drop up to $5000 to fix a place up after a renter leaves, you're not likely to be able to rent it until it's fixed and you'll still have to make mortgage payments without benefit of collecting rent. FWIW