Once you understand what numbers go into a deal and the calculations needed, you will be able to use just about any spreadsheet, plus be able to create your own.

My ROI/ Cashflow is nonexistent, I am mainly focusing on learning and I need to be more familiar with calculating those metrics. 

To evaluate a multi-unit residential purchase in Florida, what is a good rule of thumb (as a percentage of purchase price) to calculate closing costs for the buyer?

The BP calculator said about 350 cash flow.

Bigger Pockets has a great rental property calculator as well as a fix and flipper calculator and book.

I have a great deal UC and my loan officer I believe is calculating DTI wrong.

I really like the rental property calculator...

If you are a pro member here at BP they have an airbnb calculator.

It all depends on your investment plan.There is a time point you can calculate that these two choices cost the same. 

The number of financed properties calculation includes:the number of one- to four-unit residential properties where the borrower is personally obligated on the mortgage(s), even if the monthly housing expense is excluded from the borrower’s DTI in accordance with B3-6-05, Monthly Debt Obligationsthe total number of properties financed, not to the number of mortgages on the property or the number of mortgages sold to Fannie Mae (a multiple unit property counts as one property, such as a two-unit); the borrower’s principal residence if it is financed; andthe cumulative total for all borrowers (though jointly financed properties are only counted once).