Right. I'm pretty sure if you're wanting to beat the S&P 500 with a single home rental, you're going to have to buy that property with no warts or very light catch up maintenance and buy it at a 70% discount. Trying to beat doubling your invested money in 10 years with a single home rental is hard to pull off. Property tax, income tax, damage, regular maintenance, tenants that don't pay the full contract ect. ect. ect.
Apartment complexes 25 units and above, I've heard, are the way to go.
Ultimately though the best rents are storage facilities. It only requires a 60% occupancy rate to break even on annual expenditures.