When you price out the Principle interest taxes insurance and any HOA the rents in most states won't cover the payment unless you have BIG down payment or equity. 

I’m just happy to do my part for those who weren’t lucky enough to be born with my work ethic.

It can’t be a second residence because ether the JADU or primary residence must be the owner occupied bona fide principle residence.

a) you can still add to the principal so you can "carve out" your principle payment , with and without pre-penaltyb) both product is still working towards your DTI Now the challenge is the following in case you dont want to add into principal: if your home doesnt have appreciation ---> then IO only product is goodif your forecast appreciation is less than 3% and interest rate is expensive and you plan to sell within 5 years --> then IO only product is good but if your forecast appreciation is greater than 6% and interest rate is cheap and you plan to keep the house more than 3-4 years ---> then better choose 10YARM/30YFRM Meant to say this loan product is useful when one is able to visualize the amortization payment and carve it out.For example, in 2013 I purchase SF for 500K.

Pareto’s 80/20 principle will stand true again.

Yes here are some good books to read   The Millionnaire Real Estate Investor, Think Rich Grow Rich , Pareto Principle etc

Here is the NAR (National Association Of Realtors) code of ethics standard of practice defining a client and a "CUSTOMER".

And by looking deep into this or advising a client to not purchase a property along those lines is an immediate breach of ethical guidelines and violation the Fair Housing Act.

For some things you need to use ethics and just common sense to decide to do it or not.An example.

I am able to put an extra payment on the principle every year in order to chip away at it early on, but i plan on getting out of the military around the back end of 2025.