Hire a professional mason with a track record of building fireplaces. For a slimmed down version, a Rumsford kit can be installed. You still need that mason, but a manufactured Rumsford will take some of the worry out of it.

^Agreed. A Rumsford design is a proven design that works quite well for smaller spaces. We have one at our office. Many people claim to be able to do fireplaces but it takes experience to make sure it draws. I believe there is a
Rumsford design program many stone masons complete so they can be certified in the design.

Rumsford is the way to go. It has a shallow firebox and is efficient at reflecting heat into the room.