Give her 30 days notice now, keep her security deposit, and send her a additional bill for damages to the unit in lieu of taking her to court for the damages.  

For multifamily, leverages won't be as much until you have some experience not only with 1-4 units but also 5+ units. 

Investment Info:Small multi-family (2-4 units) buy & hold investment.

She wants to learn if it's possible to flip in the United States, remotely, and what that would look like.

Converting an unfinished basement into a third unit can definitely add value, especially here in Chicago.

Why 4 units in 4 years?

Quote from @Somesh Mukherjee: Hi all, I am looking to diversify & add a small apartment (3-4 units) to my portfolio.

Living in one unit and renting out the others allows you to deduct 75% of expenses like mortgage interest, property taxes, insurance, and shared repairs as rental expenses, while the remaining 25% applies to personal use.

As for valuation, I see no reasons why a Junior ADU would negatively impact additional housing unit.

Targeting single family/duplex/triplex/quadplex with 3 beds and 2 baths per unit, and $300K or less.