So I do currently have income from my rental properties, however it isnt enough to cover our current costs over here for the next 6 months.

I am planning two ADU's at two separate properties, I'll trade a large yard for additional income all day long.

This is all depending on your credit and income meeting the guidelines of course.

At this point, I would recommend having a line of credit to cover these things so you don't have money sitting in the bank doing nothing when it could be put to work.I have 33 units, no debt except for mortgages, and excellent income.

As a SFR investor for over 15 years I have been wrestling with this question in the past, because it feels like you should upgrade to "bigger".I know for sure that I would not enjoy the ownership experience that comes with a small 4F, because in Milwaukee that typically also means lower income tenants. 

From experience, I’d recommend getting pre-approved, improving your debt-to-income ratio if needed, and researching local assistance programs.

Appreciation is a real thing and not only this the demand for quality low-income housing is real. 

When you sell a property that has been depreciated, the IRS requires you to "recapture" the depreciation deductions, taxing that portion of the gain at ordinary income tax rates.

Too many low income apartment buildings near by / vacant buildings. 

More on DSCR loans: DSCR loans won't use your income to underwrite the loan.