My vacation rentals aren't in your location (we're located in the Joshua Tree, CA desert area), but just want to chime in and say that we have everything at our properties (Nintendo, tons of indoor and outdoor games, hot tub, movie projector, mortal kombat arcade, etc.) and we also have a pool table, and that thing gets used like nobody's business!

But, all you have to do is get a list of handymen, plumber, electrician, gardeners, etc., you can call if there's something that needs fixing.If the market is tight for buyers, it is probably also tight for renters and you could probably get a good tenant in there easily.You just need to be picky when you are screening. 

However now 2 weeks in a row, I have squatters breaking in through windows and kicking in doors.

One of the room mates did mention during the tour that she did but heads with the landlord sometimes because he hired landscapers to tear up their garden/didn't allow gardening, etc.

The downstairs, it's a garden-level, needed renovation.

In my experience, it's best to pay for a gardener.  

I have allowed some requests like I want to plant a garden or I need storage shelves but the sooner they start asking for changes to the structure the more likely they are high maintenence.You could also opt for a pm.

They are not only damaging your rental indoors, but they have already proved to be a general PITA time-waster.

The unit has also been tested for environmental issues and moisture was below "dry levels" and indoor air quality levels were okay though CO2 levels were just above guidelines in some rooms.The tenant is known to use a lot of candles, we're wondering if this could cause this.Does anyone have any ideas?

Because the thermostat is set so low the system continues to run under conditions it was not designed for and causes ice to start forming inside the indoor section. 2) You mentioned the service tech " refilled" the system.