I know a guy that does this. He runs his ass ragged about 18 hours a day. There's no end to the work. He's either busting his ass working on a house, trying to wrangle his subcontractors, meeting with the bank to finance the next go-around, or trying to get a deadbeat tenant evicted.
That said, he claims that it's the best job he's ever had. The cash flow is generally good, the property always is worth more when he decides to sell, and if push comes to shove on a tenant he just sells the place out from under them. Plus he has a legitimate excuse for buying all kinds of tools and shit.
His wife used to have a regular job in the real world, but upon the arrival of their first child, she started helping him with the property business. Now she handles the tenants and pays the subs, so his cash flow is actually much better. He just didn't have the time or patience to screw with it. She, on the other hand, is very organized and has no emotional attachment to the tenants, having never met them. I think it's better that way.
I couldn't do it, myself, as I don't have the patience to put up with all the hassle. However, for those that are dedicated to the long hours and hard work, there are benefits. Good luck.