I've definitely considered using my primary home's equity to put towards a duplex - hoping that my wife and I can save enough capital to fund a 25% down payment on a rental, and possibly do a BRRR method with my ability to flip the interior of the home between cabinetry and the renovation skills I've learned over the years.

All you;re doing is maximizing your cost.Second, the BRRRR method is not a method that will get you very far very fast. 

One awesome method is called the BRRRR method, which you can read way more about all over this site or in the book by David Greene.

I have only been able to identify a few methods for this based on my research.Literally spamming neighborhoods with "I will buy your house" type marketing.

Also, is there a quicker way to run numbers before doing the 4 square method ?

For example, changing lock combinations, house inspections, communication with guests, etc.

By amazing I mean very communicative, easy to work with, met deadlines, and stayed true to their loan terms. 

Hello BiggerPockets family! I am new to investing in real estate I’m currently renting my SFH out right now while I do some travel nursing around the country! 
I want to get started in Brrrr’ing my first multifamily ...

I am a Real Estate Professional and I do have lenders I communicate with.

With that said the team is always great about communicating anything that may pop up.