Our setup is weird - it's an old cape that has been heavily remodeled and at some point, when previous owners update the 2nd floor, they added ducting and just never did anything with it. So we're going to have the air handler put into the scuttle which will take care of the 2nd floor, and will be installing two ductless ceiling cassettes for the first floor. I do have some concerns about the air handler performance in the scuttle, which is insulted but gets quite hot in the summer but Carjon didn't seem concerned.