Construction project risk due to lack of equity

You are absolutely right, I just looked it up in the construction service description, it will probably cost extra:

Telephone/Internet
For the use of telecommunications services, we provide the prerequisites for basic supply. You will receive a house connection from a telecommunications service provider. At your selection appointment, you have the option to choose, for an additional charge, an internal house wiring for signal transmission to the rooms.
Television
To ensure you can enjoy full TV entertainment, we offer you the option, for an additional charge, to decide at your selection appointment to install a satellite connection. Of course, depending on the TV device, you can also receive programs with a digital DVB-T receiver with a room antenna, provided that the construction area is within the reception range of the new digital terrestrial DVB-T.

then also take a look in the provider’s model house for each room where you would like to have how many sockets and how many are actually available. You write down the difference - as long as you have not yet finally signed a construction contract, the price may still be negotiable, after that there is only a shrug if you do not want to pay the now quoted price.

The same applies to the bathroom fittings, although here you can also replace or install the washbasin, faucets, and shower enclosure yourself afterwards.

Or take a colored pencil and mark all the sockets in the floor plan that are needed for the devices already present. Then add at least one more everywhere, also one under every light switch and in every free corner of the room.

Then at least one more everywhere, also under every light switch and in every free corner of the room.

... and just don’t forget the socket next to the window on the street side!

then also take a look in the provider's show house for each room where you would like how many sockets and how many are actually available. Write down the difference – as long as you haven't signed a final construction contract yet, the price may still be negotiable, after that there is only a shrug if you don't want to pay the now asked price.

The same applies to the bathroom equipment, although here you can also change or install the washbasin, fittings, and shower enclosure yourself afterwards.

Thanks for the tip, it makes sense to discuss topics before the final agreement.

... and don’t forget the socket next to the window facing the street!

For the pedestrian to charge their smartphone or the neighbor’s Tesla?