At this point, we have users who are just getting started to investors doing over 300 deals/year all using the same system.I am more than happy to answer any specific questions you have. 

Over priced, layout is awkward, junky neighbors, back on market/under contract multiple times, bad photos, bad timing(got buried from other listings, weather occurrence, etc). 

I spoke with them over the phone a few times and they seem super pro about everything.

Have multiple exit strategies, do not be over leveraged, and make sure you are factoring market changes.

I'm happy to pass a warm referral over if needed! 

Yes I have known it to work because the owner is not a push over, enforces policy and can make it run good......however, do you have the right personality to do this, AND if you move out can you continue to have the house run smoothly with no one in charge.  

Over the years, he acquired more homes, duplexes, and even a small apartment complex.But despite his growing success, Michael had one fatal flaw—he couldn’t let go.The Burden of ControlMichael was everywhere.

It sounds like you are overly confident in your Excel spreadsheets..... 

Over estimate the costs and not need them?

I just keep hearing over and over again to just take action and course correct from there.