Is this a secure strategy for decreasing vacancies?

If you really want to decrease 1 night stays as well hook your listing up to price labs and set the minimum stay to 4 nights for days that are 20 days out.

Was it the decrease to your monthly margin from the mortgage going to rise?

Population has consistently decreased over the last 30 years and industry is not expanding.  

Corresponding  property management will decrease by 25%.

Hopefully I can help a little.So, the way we think about your question is treating your HELOC payment more as a 'holding cost' that counts against your rehab budget, as more than likely, your HELOC balance should be re-payed back down to zero, once you achieve the rehab and cash out refinance / convert the stuff to the long term fixed rate financing.Part of the benefit of thinking of it this way, is that the HELOC payment is temporary while you use that revolving line of credit. 

The population in this town has been decreasing since the 1980's. 

@Maria MarreroEven if it is $40, you still were able to do it and get it closer to market rent and decrease the amount out of your pocket. 

As a note is paid the borrower increases his equity, the lender's equity in his note decreases.2.

That would be more cost efficient in my area than installing temporary window units.