Air Flow - There is a window in the room and I have been advised that an AC unit can be added to this to keep the room cool2.

Improving the building envelope - air sealing, greater insulation - will give you more bang for your buck.

Personally, it doesn't bother me if my kids sleep on a futon or sofa bed,  but if I had to pay extra for 7 people and then they gave us air mattresses I'd be a little annoyed. 

Just curious how you go about having the discussion with the landlords about using it for air bnb?

I doubt that your road should be the same as mine, and I think you should spend some time coming to grips with what's best for your market and what's best for you. well in Pacifica you would never run your air conditioner.. matter of fact you would never need one.. 

Our goal would be to make sure the house that we are not currently staying in would be used as an air bnb. 

Where and when ane still abit up in the air .  

This would include the water heater, central air conditioning system, heat pump system, built in applicanes, etc. 

The problem with passive dehumidifiers is that the humidity is coming in with the outside air.

also, I'm told after Tenants move out with Cats to do all the Remediation work, Remove all Carpets put down new flooring, repair and clean all surfaces including air ducts for heating and air. to call an Indoor Air quality inspector and get units certified as Allergen free.