If this plan's execution is as easy as it sounds, I'll have found the perfect combination of lenders to do BRRRR until I reach my limit.

This is typically referred  to as a functional obsolescence /  super adequacy.

As a result of a combination of factors above added to the fact that I do not have contractor crews in place (as I have a full time demanding job) I am unable to proceed on my investment goals in real estate locally.

A legit lender combined with an agent experienced in flipping would be a safer approach 

Ride the market until you have enough equity to refinance into a 20-25% conventional loan package. 4plexs and 3plexs function more like commercial properties being that if they do not cash flow they are not worth that asking price or amount you are plugging in.  

Also for those 6 years, we rented out our basement so I do have experience working with renters.So now with all my background information out of the way, my question is - In forming a business and writing my business plan, do I combine my two goals into one company?

Cleaning to me is  a separate line item, but combined at tax time with maintenance.Repairs are unexpected and sometimes partial.  

To each their own.There's also the other angle, which is to legalize the illegal additions...In some cases (like where they added an extra room) it might just be a matter of backtracking a little bit and going through the city's process of pulling permits, providing drawings, inspections etc....In other cases - like if the house is zoned SFH and functioning as a multi unit - you would need the city to rezone the property...If the neighborhood is predominantly zoned multi unit, then there's a decent chance the city would consider it.

The sweet spot seems to be between 4%-5% for total commission (combined BA + SA).  

The appliances are disgustingly filthy but everything functions.