Hello, I recently purchased a newer construction home with a Majestic br36 prefab fireplace. I'm interested in replacing this unit with high efficiency wood burning unit that will heat my home (2400sq ft.) living room has two story ceilings about 18ft. The chase is located on the exterior of the home and I believe utilizes the majestic sk8 double wall pipe. My questions regarding this replacement is what can I expect as cost to have a unit installed and does the sk8 wall pipe need to be replaced or can a liner be installed in the existing pipe? I did research and found that the Regency ex90 and r90 are compatible with the Majestic sk8 pipe. Are these units worth it? I figured this might be the most cost effective considering I wouldn't need to replace the entire chimney pipe as long as its in decent shape. I am a tradesman so minor so minor framing alterations and interior cosmetic work will be done myself to reduce the cost. Any info or suggestions are welcomed. I am also a professional firefighter with a family occupying the home so fire safety is a big concern... Thanks