Property managers screw them, contractor screw them, their houses are constantly being broken into, they are getting ripped off during the initial purchase, the tenants are terrible, etc. etc.

@David Pere is the best you need to joint is IG and watch his you tube channel From Military to millionaire.I have been a follower for almost a year and due to his content I have been able to acquire more properties.

Open to joint ventures! 

When I was using PMs and their contractors, I was presented with the "plan to success" being to put lipstick on the best available properties and get 70-75% of the amount of rent I actually do get (ongoing maintenance constantly, more challenging tenant pool etc).  

The best way to learn this is to Joint Venture with someone who has been successful and knows his stuff.

I'm slowly trying to learn about retail and office, in order to diversify out of multi-family or even transition totally out of it.I don't know him personally, but we have spoken and I always see his excellent posts....but,I imagine, the good brokers, like @Joel Owens , build relationships with other brokers, investors, and businesses that are always looking for space...I bet he also, gets involved locally and meets other members of the local community and are constantly networking and trying to build and strengthen their network, in regards to commercial spaces.The right broker, that is competent and concerned about adding value to a transaction, is worth the percentage they are asking for...usually.

Mostly because their stories constantly change.

More consistent work with your main contractor to keep them in constant communication.What changes as you scale that makes it more difficult?

The only positive I see is if there is one industry with constant employment in the area eg Midland, TX - gas and oil.

To date, we've been joint venturing with other investors on flips and subto deals.