Most calls start with an open fireplace that looks good but doesn't warm the room, or a house with no fireplace at all. A mason builds a traditional fireplace of brick or stone in place. A low-mass fireplace is made in a factory and set in, and it's the lower-cost choice widely used in new US homes, so it's a fair place to start if cost leads.
If you already have a fireplace, an insert can go inside the firebox, the opening where the fire burns, and it works much like a free-standing wood stove. What will fit depends on whether your fireplace is masonry or factory-built, so that's something we settle early.
The price moves with the type you pick, the shape your chimney's in, whether a gas line and a new vent run are part of it, and the brick or stone on the face. The schedule turns on the same choices, plus any HOA or review board approval that has to come before a permit. Your written estimate spells out the materials and the steps for your house.