The entire unit is outside and will sit on the same pad as the presesnt unit. There is no "inside unit". They will need to fabricated some new duct work I am sure, all exterior though, just to fit new unit openings to existing duct dimensions . The may have to repipe the gas line a little, but it's right alongside the gas meter.

I live near the southern New Jersey coast, about 5 miles from the ocean and 3 miles from Delaware Bay. Pretty much surrounded by water on 3 sides. Winters are usually moderate, except this past one. Summers not too hot, except this one.

I am getting a couple of other quotes.