Passive income has always been my aim, and I'm understanding that real estate will be the mechanism and vehicle thru which I can achieve that aim throughout my next decade(s).I drive around residential neighborhoods on a daily basis and have begun "driving for dollars", or at least identifying potential wholesale properties.  

@Cory Mccarthy I recommend Bill Kaiser with All Weather Mechanical.

Of course if your plumbing to the STREET is brand new and you have new pex... you have new wiring new roof New mechanicals.. the rest of cosmetic if the house has good bones.. that helps for sure. its hard to make a case study with just one home.you could also have one were the tenant left at 5  months and did 5k of damage.or you could be buying in Dallas area and have your foundation go wonky and spend 3 to 5k fixing it .. which happens on almost all homes in that area. etc etc  some of this is regionalize for sure.

I had just hoped that someone would know some legal maneuvering, where we could put a mechanics lien against his property or similar

@Julie Marquez there isn't really a mechanical difference caused by having tenants. 

MEP Systems (mechanical, electrical & plumbing)The kitchen and bathroom plumbing is assumed to be included in the Kitchen & Bathroom allowances above. 

I use technology to help with auto responders and the like.

If this is a flip and you don't pay him, what are your plans if he puts a mechanic's lien on your property and you can't sell it until it's resolved? 

You get a Realtor to put you on a daily auto email for certain kinds of properties you want at below 70% of the average price/sq ft for the area or listings with certain motivated seller keywords.

Don’t get me wrong, the way you’re learning to run the numbers is great, that’s an important part of the process, but you also need to learn as much as you can about local markets, building construction/condition/mechanical systems, and property management/actually running a property in order to be able to assess the overall quality of a property to know if it’s a buy or a money pit.