One thing to watch out for... it is a tax, but not an income tax (so it applies to Roth accounts as well). 

I watched some of your videos on YouTube and was impressed.

If you're in the real estate investment business and must watch every penny, irrespective of your time, then by all means, do what you think will keep your expenses to a minimum.If, on the other hand, you are really in the business of creating profit by way of being a good marketer and a committed dealmaker, your creative energies ought to be reserved for doing what you do best (or intend to do best)...

There are multi-million dollar houses that you can walk just a couple short blocks and watch the neighborhood get pretty rough and potentially dangerous.

As you read these books, watch the BiggerPockets podcasts.

I watched a bunch of the OwnerRez videos and honestly OR and HA look eerily similar. 

As others have said watch out for property taxes and home insurance too. 

I love Ben and his family so I'm glad you're watching his content.

Largely is because renters are not going to watch their electricity usage patterns, which makes it is hard to dial in the right system config to anticipate the load.

WE took 16 40 yard dumpters off of that house property and various vehicles etc etc. there was also a live boa constrictor that scared the heck out of one of the workers it got away ( of course) and the police wanted me to walk to all the neighbors and warn them to watch out for their cats:)WE demo's the house and I built a 1.5 mil dollar spec on it.