I hardly ever touch door locks other than set some one time codes for a contractor or change the batteries. 

Stayfi for email capture to build out email listSchlage Encode for door knob - easy check in code creation. keep lock box somewhere on property with a physical key in it in case battery every dies or lock doesnt workPricelabs - pricing automation. however I do organic pricing.

I manage remotely from another state, so I also have a lockbox with a house key at my STR in case the Schlage battery dies, wifi goes out, or it stops working for whatever reason. 

Domestic calls, battery etc.Also on the repairs....if you haven't found a solid handyman skilled in pretty much all trades Id really make an effort to do so.

Large corporate holdings can make sense of ratio analysis due to the size of pools held, mom and pop do it for fun to wear out batteries in their calculator.Ratios then become relevant as historic measurements not so much as a projection for a buy decision. :)

I get a full "Spring Service" including changing out all HVAC Filters, Smoke Detector Batteries, Sprinkler System check and repair, and a complete inspection by a Professional Contractor for a cheap price. 

I mostly blame my naiveness in humanity and eagerness to get the project going.. here are many of the items (not all):All 3 HVAC units went out in the first 3 monthsBoth "high end" endless water heaters died within 6 monthsThe 1918  LEAD pipe entering the home burstSome lighting was found to be battery operated instead of electricUnfortunately a rock from DC water entered the piping which resulted in multiple cancelations and major repairsNo insulation between the upper and lower unit resulting in numerous noise complaintsPitch incorrect in back yard which results in floodingPlumbing piping incorrectly sized throughout homeAll gas lines removed and everything replaced with electric to pass city inspection easier (only house on the st without gas)Oh yeah, furnishing a two units that can sleep a total of 16 people is not easy nor cheap (especially with a puppy).

For example, remote batteries didn't work so we couldn't use blah.....we store extra batteries in all of our properties.

The checklist requires many things including checking oil, fuel and battery charge levels and then requires one to turn on the system and make sure it runs properly.

Keep parking area clean; Residents must keep vehicle parking areas free and clean of garbage, personal items, and any vehicle parts or fluids, such as oils, coolants, spare tires, batteries, etc.iii.