It works. There honestly is not much to it if you are even somewhat handy (i assume most on here are).
The biggest issue for most people seems to be finding the motivation to just do it! Once you get started, you will be surprised how easy it is.
Once you get the snowball rolling you will ask yourself why you did not do it years ago.
Once you get the first house paid off (hopefully soon for me) and you see an extra 10k on your annual salary then the snowball can really pick up steam.
My advice is to buy smart, never use a real estate agent (they eat into profits and for $600 you can hire a good real estate lawyer to handle things for you), and just buy good bones.
After that the operational side is my least favorite but once you get a system down for finding and retaining good tenants then it gets better.
I am looking at my 5th rental to possibly purchase later today. This one has a big enough garage that I could wall off the entire back half, add security and temperature control for a little money, and have enough storage to fit all my current overflow