Negotiating favorable terms like a low interest rate or interest-only payments for the first few years could help manage cash flow until renovations are complete.

We have been in real estate (long-term rentals) for over 20 years now and looking forward to hanging up the maintenance hat.

Also, what are some other low cost amenities that I can add to my STR that will yield a higher ROI?

We are looking for low maintenance (so primarily new construction or >2000 and well maintained/rennovated) single family homes.

I find the savings from not needing to add chlorine is instead spent on chlorinators.I would not use salt for an only a spa because the chlorine use is so low.  

@Stephen FlemingFrom my experience working with over 400 investors, your strategy of leveraging a low mortgage rate, tapping into home equity, and diversifying with a short-term rental (STR) in Northern Michigan is well thought out.

@Tamika Davis One of the biggest advantages of most software on the market is to complete these tasks you mention (maintenance, leases, rent collection, etc). 

2) Maintenance Reserves: So many factors here to consider!

. - low vacancy.  

It was high rent, low entry point area but within 6 months I dealt with an eviction and electrical issues.