With 1.2 you may have to opt for a bridge lender, provided there is value-add component that can push your DSCR higher.Of course, initial DSCR is inversely proportional to your purchase price: the higher the price, the lower is initial DSCR that is based on the current income.

You may wish to maximize contribution to a Solo401k first because you can elect to have a Roth component as part of your Solo401k.

As @Christopher B. pointed out there are many components to be considered, and quite frankly many more.That being said, "How do I get an actual cost estimate" and "where would one find an investor, if needed". 

Do you guys put separate systems in each unit or do you put one base station in one unit and connect all security components in and around the building to it?

For newly constructed, purchased or renovated properties and also retroactive generally over the last 10 years, building components are properly classified into individual units of property and accurate recovery periods for computing depreciation deductions.

The "Wall Removal" component woould prompt the requirement for a full building permit compared to a "Pull and Replace" Easy Permit option...

All major components replaced within 5 years expect windows.

All the components other than ducting are on the outside of the house and they're used where space or ease of installation is an issue.

I'd recommend that you chat with a mortgage broker for confirmation and make sure that your income (with a commission component) has been properly recognized.

Consider Their Maintenance PlanRenovating damaged components or appliances when a problem has worsened costs significantly higher.