I had access to a legal and compliance team to assist in doing such, as well as my background in contract law.

I am guessing it'd be a 30-40 day close?

My wife last year closed 28 million by herself NOT a team thats by herself..

I am wondering how to easly  integrate rental forms ( I use WI Legal Blank) into my landlord software (I am using Simplifyem).

The replacement cost (cost to rebuild, not the value of the property) data providers are pegging the quadplex at close to $2M and most 1-4 unit rental property insurance programs tap out at $1-1.5M before you'd end up in a commercial insurance product.

I find it hard to believe that there were no signs of any friction or issues that could have been uncovered in the years leading up to the legal split.

Of course not, you still have a legal tenant.

I think hard money lender to take this risk cannot legally charge appropriately which means the law is working against you (the law meant to protect owner occupied owners from unfair loans).I agree with @Jay Hinrichs that your best option likely is to sell on the mls.  

We now are looking to create an LLC and setup the necessary legal documents to protect both parties and layout the terms of the agreement.

Lets say your accountant tries to write off as much as is legally possible when it comes to lowing your taxible income so that your tax burden is less and you pay less taxes.