The costs of the chimney system are always calculated separately. There are several reasons for this:
Chimney systems are fundamentally different. Accordingly, different installation costs. To build a brick chimney for a long time with cheaper source material. Install a modular system of stainless steel very quickly at a fairly high cost for the components.
The chimney can not be installed at all by the stove-maker. There are third-party organizations that specialize in the installation of a chimney system.
There are often options when the chimney shaft is carried out by builders during the construction of walls.
They even mount a sleeve or a whole chimney. Here, the stoveman only performs the connection of the consumer to the receiving pipe of the chimney.