We are considering buying a house in Somerville, MA and it has baseboard heat. My wife HATES that kind. I hate window ACs as much. We are probably 2 months away from being ready to make an offer so I am doing some budgeting. House has basement and 3 floors. Total 1400sq ft. with top floor not heated (but finished). I have found some small articles about retrofitting that kind of house with high-velocity HVAC (the ones with 3-inch flex pipes). Are there any better resources out there on the web where I could read up on those systems or other options? I want to be knowledgeable about how those systems work and how much I would have to tear up the house to get that in (hence $$$?).