Mainly you're responsible for the sewer bill and to provide heat and hot water, but not things like air conditioning.If this was winter, I'd be concerned about pipes freezing if the relationship isn't going well, but a 10 year tenant probably won't let that happen.I don't really know about the downsides of not having a lease. 

I'm not familiar with vrbo and other sites- but you could at least set up your own dot com booking funnel/site & (legal- per air bnb -personally don't know?)

Are these related to the air conditioners, or do they control the electricity for the entire house? 

Compete with new constructions with upgraded as granite or Quartz counter tops, central air and heat,and in unit laundry.

I look at a recession more like a thunderstom that clenses the air.

They do not add more for garage, basement extra storage, central air conditioning etc, which are market rent additives. 

We recommend purchasing travel insurance to protect your funds from the uncertainties of mountain travel, including the possibility of snow storms, road closures, and poor air quality due to wildfires.

It is in the Beverly Glen/Bel Air area. 

Air leaks around these openings are often pretty easy to improve.

Last weekend it stopped to work again but heard loud sounds in the air handler.