After some time we are able to renovate with new flooring, new paint, new light fixtures, new bathroom fixtures and vanity, new kitchen countertops, and painting the kitchen cabinets and new cabinet hardware for about $7500 on a 1/1 or 2/1 apartment.

"Modular" structures are allowed to get a CofO in the US if they're IBC/IRC compliant -- which requires someone to do code compliance checks on the factory floor.

Full kitchen and bathroom remodel, new floors, drywall, interior and exterior paint, landscaping, and misc.

Sure, house hacking is finding a house that can reasonably divided into two areas allowing you to sublet one side or one floor of the house while also allowing you to live there. 

The unit that is not updated, I've already done significant upgrades like flooring, new trim, doors, appliances and current tenant accepted my increase to $850/MO.

I would be living on one floor and renting out 2 bedroom on the second floor (they would have to share a bath.)

Knowing where to take financial shortcuts (floors) and where to invest (fireplaces).

Title, appraisal, recording, insurance fees have the same floor of minimum costs.

Modern floor plans, modern mechanical systems, well insulated, generally separately metered etc.

Porch floor, painted foundation exterior, bathroom ceiling.