The less guests that use the grill the better, I imagine not providing propane decreases their chance of using it.

Without some local tax incentive, I would actually expect your taxes to increase, not decrease, as a result of your improving the land.  

Rates have doubled, while home prices have barely decreased in most markets.

With a potential sharp decrease in STRs in the area the continued demand from tourists will also offer a potential increase in rates that will offset the days occupied by me, my family and friends. 31 days is roughly 8% of the year.

. - Price decreases- Days on market - Expired listing- Active/under contract 

I moved to the area in August, and have definitely noticed a decrease in home prices in the area.

The decreased size can cause carbon dioxide to fill up in the basement, this could cause injury and death to your entire family"While both are technically correct, One gives you an idea to repair, the other has now told you if you buy this house your family will die.Good Luck!

Beyond this, the relevant cash flow metric is your Cash on Equity return - this is the amount of net cash flow the asset generates as a function of the amount of equity you have in the property, and will (generally) decrease each year as you equity increase will outpace your rent increases.

I am still researching multiple markets and couldn't for the life of me understand why I saw some tax years jump or decrease 2x what it was the previous year.  

Multi family is all about increasing income and decreasing expenses as this directly influences property value.