Your best bet is to call a real estate attorney and ask for a consultation. 

The due on sale clause generates a lot of debate on biggerpockets, but me and my colleagues have yet to see a performing note (a mortgage that is getting paid) get foreclosed on based upon that clause.

I own a performing duplex and have successfully flipped one single-family residence.

Is there a way to do a market analysis similar to what a Realtor would perform if selling or buying a home?

No worries about a seller sueing for specific performance.  

The good thing about holding them is that most are rented and performing.

I tried just surfing for awhile to catch up but honestly our best bet is to just dive in!

your best bet is to just sell a partial.. just a few years of the cash flow you won't take such a dramatic hit.. although myself I would not be keen on a 1 bd home incase I had to own it.. and I would want to know that since you sold it to a homeowner that you did full dodd frank compliance

Rental rates are increasing steadily and I could see this market end up being the top performing market in the country when 2016 comes to a close.

I'll bet you can replace the lost revenue {much} more cheaply buying another 4-6 unit.What is the zoning for the area (not just your lot)?