How best to seek one out without charging an arm and a leg for simple phone calls, etc.?

@Tom HunterTo find a good PM and possibly a deal go to IREM.org search for ARM certified property managers.

The three approaches to value used in residential appraisal are focused on arms length transactions between two parties of sound minds.

Well actually my goal is two analyses a day, not really a truckload, but I do feel I'm arming myself properly.

The 2nd mortgage will be a HELOC ARM at a higher rate, but that 80% majority shouldn't be too far off normal.  

You'd need to sort out all of that in advance and make your lease really explicit about the arrangement, because it seems like they could be easily taken advantage of if they don't completely understand the setup.  

@Ashley WolfeGoogle the property name and address see what pops up.To find out about an areas go to IREM.org search for ARM certified property managers.

I have seen it all. and if it was not for me back stopping these arm chair rehabbers there would be carnage and a lot more blood in the water. your concept is good but I think its wishful thinking for all but the most experienced.. and not a model someone new to the business can just go out and create.. they just don't know what they don't know..

If it's a good business decision that won't cause you to lose your mind, perhaps reengaging with explicitly clear terms may not be the worst decision. 

While a sibling can loan your IRA LLC money as they are not consider a related under the prohibits transactions, but it has to be an arms length transaction, basically rates and terms a completely un-related party.