So with us, the general contractor charges about €135 per installation point (that is without light bulbs, but including wiring).
Concrete recessed pot of the type Kaiser 1282-40 mounting housing, HaloX 180 with tunnel and transformer channel.
Additionally, the appropriate cover with a diameter of 180 mm, so that positioning inaccuracies can still be compensated later.
The calculation for us is based on electrical units. Here one unit costs about €60 (e.g. for a socket or a simple switch, or a connection point for a ceiling or wall light, etc.).
He then adds a surcharge for the concrete recessed pot so that the total comes to the mentioned €135 including VAT.