Is it a “bad” decision to put 20% down on this multiplex, likely have most of the mortgage covered by the rental income while continuing to pay rent at my current apartment? 

Inspect well as Miami is notorious for illegal and non-permitted additions.  

My question is: can we use projected income from the other units that we wouldn’t be living in to help get approved for a mortgage?

Try to find a way to increase income $80.

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.

We can educate and get you straightened out.Benefits of whole life insurance include:* Income Protection (Disability/Illness)* Flexible Access to Cash* Tax Advantages* Stable and Guaranteed Growth* Asset Protection* Legacy and Wealth Transfer* Uninterrupted Compound Growth* Ability to Earn in Two Places at Once* Inflation Hedge* Dividend Potential* Non-Correlation to Market* Life Death Benefit Coverage* Tax-Free Retirement Income Potential

DSCR is a great tool to use when you are self-employed or you want to avoid using personal or business income to qualify.

Dive into rentals to get more monthly income coming in?

Additionally, nothing can be enforced without a system to challenge the enforcement. 

It's not the easiest way to make money, you need to stay on top of the logistics of things, and keep a good relationship with FedEx, but it's steady money, and once the route is established and you have some reliable drivers, it's good income.