You can easily get screwed over with the size of your HVAC. Size matters in terms of heating plus cooling. If the HVAC is too small, it will run all day long. The HVAC will work plus work until it burns itself out. Then a hefty HVAC repair is needed or the HVAC is just plain done for. Super expensive or cheaping out with tiny HVAC? Too sizable of HVAC component is no better though. The HVAC is then always cycling on plus off. The powering up plus down is exhausting for the HVAC unit. It will also cause injure in this process. It also is exhausting in terms of efficiency. It is better to keep a steady stream of heating or cooling, powering totally on plus shutting all the way down takes way more power to do. The HVAC will end up costing more when it runs half the time. Most HVAC providers try to size up with HVAC component too. What they do is called rule of thumb. Basically the HVAC guy walks around a beach lake house plus takes loose measurements. He eyeballs it plus then pads his numbers up for error. Then, the HVAC professional recommends a size for the home. The larger the HVAC, the more commission. So those numbers get padded quite high plus the homeowner usually gets stuck with way too much HVAC to handle. Do a little research before making the sizable leap on HVAC. Decide what type of HVAC you want plus what is the advised size for your square footage. Take the HVAC company totally out of the equation.