I gutted it and added new drywall, new light fixtures, new bathrooms, new paint, new kitchen, new furniture and new flooring and new windows.

Take your time and trust your instincts!

., cosmetic fixes rather than full gut rehabs) might be a safer entry point.

Your remaining balances weren’t entirely clear on the two mortgages, they are really low rates, so instinct is not to refinance them, but sometimes it is worth it for the longer term vision.It also seems like you may be considering tapping your equity to replace your income, without knowing your age or long term goals, this doesn’t seem like a great idea on the surface.If you are interested in jumping into real estate full time to replace your income you should realize that is probably going to take 12-24 months.

The reason I know this is because my first duplex was a complete gut, I had no clue what I was doing I just believed in the end result and trusted the people I was connected with locally.  

I am debating about the converting the existing old gutted building to either multifamily building (6 units each around 500 sqft small studio) or mix of 4 residential and 2 retail/restaurant conversion (the back side of the property has Big enough lot for outdoor dining or any other use cases.Any recommendations for use case of pure multifamily or mixed of multi family and retail?

Flooring, Drywall, refinish basement, roof, gutters, tuck point around house, and one full bathroom gut all had to be completed. 

The layouts are funky, often poorly done, and if they haven't been rehabbed in a long time then you need to likely fully gut the darn thing3.

My gut tells me that Homeland Security was one of the agencies he reported the “alleged” fraud to, and anything further was wishful thinking on his part.  

Sellers have intuition and instincts.