Without solid knowledge on this subject, you can easily end up in hot water. 

The yard looked like trash, plumbing stack leaks and multiple water heater leaks.

If it can be used as a STR it's going to have septic, well water and need Starlink for internet.

Be sure to have the gas, water and sewer lines inspected as these may be dug up or collapsed - and very expensive to replace/repair.

The interior was made up of high efficiency HVAC systems, contemporary lighting, and electric water heaters.

I assume you are mostly looking for leaks and water damage?

(normally recommended, especially if you are a landlord)- Water Backup: For water damage due to the backup of Sewers or Drains.- Personal Articles: Coverage for belongings that have a special or collectors valuesuch as Jewelry, Furs, Fine Arts, Collectibles, etc...Your age should not be a factor on the pricing but, depending on the company these other factors may get you credits:- Insurance Score (company pulls certain info out of your credit report).

water heater? 

Quote from @James Jefferson: Hi, I have a family member that had a reverse mortgage on their property it's a 3b 1b 1 acre of land heats by oil no hvac and on well water.

The only thing that sounds out of the ordinary here is the water bill