And in section F-908.7.5 it stated that owner of the building (landlord) shall post a notice in common area and inform tenants about CO alarms and provide with manufacturer instructions.

You'll be ahead of the game by skipping an architect and going straight to a self storage conversion kit manufacturer like Trachte or Janus. 

The maximum number of financed properties that are permitted is based on the underwriting method, as described later in this topic.The financed property limitapplies to the number of one- to four-unit residential properties where the borrower is personally obligated on the mortgage(s), even if the monthly housing expense is excluded from the borrower’s DTI in accordance with B3-6-05, Monthly Debt Obligations (01/30/2018);applies to the total number of properties financed, not to the number of mortgages on the property or the number of mortgages sold to Fannie Mae;includes the borrower’s principal residence if it is financed; andis cumulative for all borrowers (though jointly financed properties are only counted once).The following property types are not subject to these limitations, even if the borrower is personally obligated on a mortgage on the property:commercial real estate,multifamily property consisting of more than four units,ownership in a timeshare,ownership of a vacant lot (residential or commercial), orownership of a manufactured home on a leasehold estate not titled as real property (chattel lien on the home).Examples — Counting Financed PropertiesThe borrower is personally obligated on mortgages securing two investment properties and the co-borrower is personally obligated on mortgages securing three other investment properties, and they are jointly obligated on their principal residence mortgage.

You'll need to find an escrow agent that deals with manufactured home and understand what you're doing. 

But my friend had a spare weekend to do the sanding, so I took the help while I could get it... fortunately I work at a manufacturing plant, so there is plenty of cardboard and fabric laying around I’ll put down now.

There are alot if of mobile home parks and manufactured homes that are being bought torn down and all kinds of different types of homes, condos, and townhomes being built. 

Our current space is zone for light manufacturing and given my father's business model we need the space. 

Definatly looks like manufactured home dry wall without the joint strips. 

Does this sound like a good deal 4 mobile manufactured homes (230,000$ for all 4) Each house is approx 1600 Sq.ft 4 bedrooms, 2 baths, Laundry roomNear shopping & businessesWhat will be my assignment fee be for this?

Commercial Lender HELOC any different for manufactured on own lot?