What you will be required to do is register as a foreign entity in the state the property is in if it’s not the home state.I recommend speaking with an attorney and your cpa on if a LLC is even required and the state(s) to incorporate it in.

Or if the home was build in 1980's maybe the plumbing is polybutylene and again, will require whole house plumbing. 

Also what platform(s) are you using to create and host your website (wix, wordpress, squarespace, etc)?

I would say its extremely important to have a quick (like 60 second elevator pitch) for why you want to enter the business and what returns you are looking to get. 

@Jeff S. 

The question is not does OPM “Exist”The question(s) is (are)1.

I suppose it could be more of a semantic thing, but seasoned RE investors understand it isn't all about the unit #'s, especially when it comes to section 8.

I bought a house less than a year ago in the 160's that was a completely remodeled 2bd/1bath that turned into a rental when I moved.  

Rates are typically in the 6's right now give or take.As for challenges, make sure you know if the proprety is rural or not because that will likely affect LTV.

I shot you a message but I do RM-1 s all of the time with my contractor and can give you some more insight.