Are connection costs for electricity and water doubled for duplex houses as well?

I would be interested in your experience building a semi-detached house. We are building a semi-detached house (we own both halves) and are currently dealing with the connection to the electricity and water networks. The plan is for us to do all the excavation ourselves from the start of the property to the utility room, and also lay the empty conduits there. Since both halves of the house are to be supplied from the same connection in the street, everything from the sewer/distribution to the property boundary only needs to be dug up once. Now we have received the offer from the network provider and, to put it mildly, we are shocked. The bill is supposed to be charged twice for exactly the same amount because there are two houses with two different house numbers. Is this actually the usual practice? I find it outrageous, especially since we are doing most of the work ourselves. The costs for the small stretch (5 meters) on the street and the connection inside the house amount to 2x 8,000€. Has anyone here had a comparable situation before?

Now we have received the offer from the network provider and are, to put it mildly, shocked. We are supposed to be charged twice the exact same amount because there are two houses with two different house numbers. Is this really common practice?

Whether this is common practice, I don't know - but in our case it was the same.

Check the network provider's terms and conditions again to see if own work is actually credited (did you communicate that?). Normally, this is included in the connection price up to a certain length, and you can then reduce it with own work. But the amount applies per connection, that is correct. So if you had a joint connection (with only one meter), then it would only be charged once.

That you have to pay twice is normal, as there are two independent connections, but €8,000 really seems expensive to me. Especially with so much preliminary work on your part. We paid €4,000 for our 5m including everything with no own contributions. I would call and clarify that politely. Maybe something can be done.

The civil engineer from the [Stadtwerke] will come anyway, and they usually don’t charge for the 2m cable trench you dug yourselves. Mainly because the meter price is a mixed price for digging up, material, laying, filling back, and restoring the surface, i.e. compacting for example. None of this is itemized separately and therefore cannot be taken out separately.

By the way, anyone who has ever dug a 1m deep and 50cm wide trench into the compacted foundation cushion around their house... would rather have the [Stadtwerke] do it for 100 EUR/m all-inclusive; it’s the worst kind of backbreaking work by hand. There is enough to do on the house where you can exert yourself physically and save significantly more. Save your strength for that.

Oh, I see. Legally speaking, there are also 2 trenches on the street. Because there are 2 barrier devices, 2 couplings, 2x PE pipes, 2x NYY 5x35... since this is not separated individually from the civil engineering work, a discount might be possible, but that is goodwill on the part of the municipal utilities. Legally, they are certainly allowed to consider these as 2 separate house connections. The fact that they only made one trench, so how they carry out the work on public ground specifically, is actually none of your concern.

Oh, and as a rule, each connection also costs a flat rate, plus the meters. The flat rate is paid in full by each connection user in any case.