CPR the parcel and plan to sell the CPR ADU and then build the Second farm dwelling of approximately 3,000 SF.

I know as a vacation home you are expected to dwell within the resident for at least 14 days of the year, but other stays that might be needed for upkeep might be write off costs? 

They also don't make as good as an investment as a more expensive, traditional single family that will appreciate 3%+ per year.The best way to live frugally but comfortably is to max out your pre-approval and buy a multifamily property or single family with an ADU (accessory dwelling unit).

The property I'm interested in is the layout as a duplex but I can turn it into a 4plex by changing the layout around and adding walls, 2 Kitchens, and a bathroom on the title it is a single-family dwelling but how do I turn this into 4 units legally so I'm able to cash out refi.

Lots of properties with mother in law suites and other accessory dwelling units called “carriage houses”.

They should be able to cover over your home, ARI, & rental dwelling.  

The number calculated based on these inputs are estimated property value, estimated monthly rent, monthly maintenance reserve expense, total monthly expense, pre-tax profit, after-tax profit, cash on cash return, instant equity, and 10 year projected equity gain.Any constructive feedback is appreciated, as I want to make sure I 'get it right.'

The building is zoned RT-4 in Chicago, and as far as I can tell, there is a minimum requirement of 1000 square feet per dwelling unit.

The comps used are single family dwellings, and our ADU is being considered as a "guest house" and an amenity to the main dwelling.

Most people fail because they want instant gratification.