everyone else has already left great answers, I just want to add if you are purely a buy and hold investor: using bonus deprecation aggressively as early as possible is usually a great way to go. 

This is what I would do if starting out in real estate and wanted to buy my own home and start getting rental income and experience.

Hey Folks,I'm under contract to buy a 4 unit building, 3 prime residential with ground floor commercial.

I would like to buy a duplex and try an airbnb and if that did not work would like to long term rent the property.  

. - What markets are good markets for investing/buying large multifamiliy apartment complexes?

You need to have a property under contract that meets a buyers criteria or you can start networking with investors and find out their buying criteria. 

She has been trying to BORROW the funds she needs $550K to pay off the Husband and another $300K of additional funds (Totaling $850K) so that she has the EXTRA borrowed funds to be able to make 2-3 years of payments on the financing (versus raiding her retirement account).

The commercial returns available on loopnet or auction sites for public viewing generally seemed no better than I could’ve gotten buying overpriced residential property.  

@Michael PaywalaI am a multifamily investor located in Greenville SC.Always looking to buy more apartments.Maybe we can meet up when you are in Greenville sometime.Arn

A PM would have taken most of that.I have seen too many OOS investors fail buying cheap properties in rough areas not recognising that over time capex exceeds cash flow.