To further answer your question: the truth of is subto legal is “it depends” - now is it criminal - most likely no - but could it be illegal yes.

Phase #1 - Recovery  - characterized by high vacancy rates and no new construction- rent, during this phase, is flat or declining- owners offer rent concessions to avoid their property occupancy rate from  decliningPhase #2 - Expansions- characterized by declining vacancy and the start of new construction- occupancy improves, concessions are not being offered, and rental rates being to growPhase #3 - Hyper Supply - characterized by new construction and vacancy rates beginning to rise - rental rates begin to grow at a slow rate- rent concession are being offerred due to the new construction in the area [in the hope of retaining current renters]Phase #4 - Recession - characterized by the completion of construction and a decline in occupancy rates - concessions are abundant to avoid high move-out rates Here are some foundational truths about optimizing your investments:#1 sow seeds of success in the down times - "The season of failure is the best time for sowing seeds of success."

Do you know if there's any truth to that, or have you had any of these issues affect your investments so far?

In truth we could have started with 10 great ones and wound up so much better off over time Powerful advice!

Half assed truths exists forever on the internet. 

I have never heard of any NAR agreement for agents to be involved with notes, that is far from the truth.

But a bedroom or a bathroom can be easily qualified in terms of dollars (I usually see $4,000-$5,000 allotted for differences in bed/bath count).Truthfully, if I can't find easy comps and if I can't make it easy for the appraiser to agree with the value I'm looking for, I just don't buy it.

That couldn't be further from the truth!

Truthfully though, I would do a cash out refinance for a large sum of money on my primary residence to ensure I do get a better rate. 

What you have done is effectively refinance your mortgage at a lower, albeit variable, rate.If you go back a couple of years in this thread, I posted a series of spreadsheets comparing variations one of the cases originally presented to sell this approach.If you were to model making more frequently (i.e. accelerated bi-weekly) mortgage payments and augmenting these payments with additional principal payments (the amount you currently apply to the HELoC), my conjecture is the gap would be rather narrower.