Sage, I cannot argue with experience and Rich seems to have it in abundance. However, another thing Rich has in abundance is MONEY, so he can be selective in his purchases. Yes, the ideal SFR is 3/2 1,500-2,000 sq./ft home. Not too big not too small. Your typical average family home which runs on the average, west to the Mississippi at $80K-$150K in most areas. However, cash flow is questionable especially if you go by the 2% / 50% rule.
If you are short on money, However, or not so loan-worthy, there are other areas where those averages don't play. In the "Old America" (East of the Mississippi) in many cities in old neighborhoods the norms run in extremes. They used to build three type of houses 2/1 or 3/1 for the common workers 5/1 & 5/2 for the upper management or bigger mansions for the owners. Over times when factories closed down the lower middle class moved to the bigger houses and the low class move to the workers' houses. (Now they are all mixed. There are beautiful Victorian and Arts and Crafts mansions smacked right in the middle of war zones)
There are areas like Hueytown, AL where most of the houses are 2/1, you cannot find a rental. They are snatched before the tenant is ready to leave.
Three of my SFR in Birmingham are 2/1. However, in one case I converted an enclosed balcony into a bed room (Slapped a closet and vuala ...) In the other one I created a bad room in a partial basement and the third one is actually a room, but again I need to put a closet in.
All of those properties were bought and rehabbed for less then $30,000 each. Those also, extremely good cash flow.
You can get good investment as Rich mentioned with probably better prospective of appreciation, but for three times as much money.