With air conditioning you can choose to go ductless or without.
A ductless mini split or heat pump is constantly a smart option for Heating plus A/C for the home.
These options provide btoh heating plus cooling plus the way it operates is efficient. You take existing heat energy already in the air plus use it. Most systems have to burn a fuel which isn’t efficient plus takes awhile for the cabin to heat. The air quality is dry plus stuffy since it is the same air being recycled. With a ductless system, it is much fresher. However, the indoor air handlers I constantly find to be a little bit of an eyesore. I don’t prefer the idea of mounting sizable metal boxes to our walls. I also don’t prefer the outdoor air compressor on the side of our house. A central Heating plus A/C component seems to be a fan favorite. You don’t need numerous indoor units plus thermostats. You have 1 indoor component usually hidden in a closet plus 1 hallway thermostat. Then through HVAC duct, each room of the cabin gets equal amounts of heating plus air. Everyone is ecstatic. Well, not everyone has the same temperature preferences. If you live alone or don’t use certain rooms, this is not all that energy smart. Some people choose to have the best of both worlds. You can get a high velocity AC idea that uses stretchy HVAC duct that is half the size. It can undoubtedly fit into an older cabin plus provide ample cooling in half the time. It is a bit costly however worth the price.