All of us just built a family room addition onto our beach house as section of a beach house renovation project myself and others and wife did, however everything is pretty much done except getting heating and A/C into the family room that every one of us had built onto the house.
All of us had thought about getting a ductless mini split A/C and then having it converted into a full on ductless heating and cooling unit.
However, that would prove to be more expensive than just having additional HVAC duct laid and created. So that was what every one of us decided to do. It was pretty easy surprisingly. All I had to do was call the local heating and A/C company to order the work. Then it was a matter of scheduling a few days in advance to have them send out a crew of certified heating and cooling specialists to come and both build the add on needed and then kneel the additional HVAC duct. That way every one of us would not have to invest in any additional heating and A/C equipment. All of us could just have our regular central heating and A/C toil for the new family room as well. All of us had the HVAC duct built and laid within 2 weeks of making the decision and making the PC call to the local heating and A/C corporation. I was pretty ecstatic with the overall results, then our family room now has the same great and most powerful heating and A/C as every one of us do throughout the rest of our home. It helps that every one of us recently purchased a brand new and up-to-date central heating and A/C unit.