I believe this topic just came up a couple days ago.

@Ben Leybovich Global financial policy is far too complicated to hash out here, but I'd suggest if you want to know more on the topic you, google can help.

I understand that this is a very tough topic, because every deal is different.

There are also plenty of threads here on BP that go into much greater detail on the topic. 

Does anyone have any insight on the topic or know any loopholes that would allow me to legally purchase investment properties using residential mortgages under my LLC?

Other topics too. 4.

Check this link: https://www.biggerpockets.com/forums/12/topics/727375-legalzoom-vs-local-attorney-to-form-llc

It might be worthwhile to have someone help you sort this part out.As an example of what can be done in Phoenix, you can see a sample herehttps://www.biggerpockets.com/forums/311/topics/780022-3-ways-to-wealth-in-real-estate-cashflow-flip-hold-here-s-how 

What are your favorite books that cover these topics?

I haven't been able to find much information around this topic so I admittedly may be searching for a unicorn.My scenario:  I have a (2-4) unit multifamily with serious rehab that falls very close $1M ARV.