I don't imagine a variable rate HELOC has an interest that much higher than 7.5% at the moment.

What variables should I consider?

It's really going to depend on what your wants, needs and desires are with the property and what level of comfort you have with being remote with respect to the different variables necessary to run a successful VR.  

@Jaime PinedoRisk variables that might impact cash flow include market fluctuations, economic downturns, and unforeseen costs.

This is the big variable here.  

This shouldn't be a the key determining variable for you, but it's worth noting that you couldn't sell a property in Puerto Rico and do a 1031 into another property in, say, Florida or New York. 

Basically, you are trying to isolate the different variable to best estimate the market's effect to it. 

These rates vary depending on a lot of variables but the comps are pretty strong for the most part.

Do you charge and how much.Acceptable Vacancy Rate - we own a reasonable # of doors in the city of Milwaukee - not great areas but not horrible either.Thanks in advance State laws dictate what you can charge for a late fee (in DE we have a 5-day grace period and the maximum allowable late fee is 5% of the rent amount) so look at your landlord-tenant code for this.As far as pet fees, it is also capped per the landlord-tenant code for our state at one month's rent.Too many variables to address your vacancy rate question.  

This will reduce your turn times allowing you to scale much quicker... not to mention reduce the unknow variables that come from having to wait for longer seasoning periods.The main benefit I see with a DSCR Loan is you don’t have to provide your tax returns and provide the documentation on all your other properties.