Earthworks - Costs without order or agreement?

First of all, so far we are very satisfied with our developer, and our building expert (employed by us) can only sing praises as well, but now we have an issue for the first time and before we argue we want to clarify whether we are in the wrong.

We have paid approximately 5000 EUR for the earthworks listed under 2.0 in the payment plan, now we have received a second invoice amounting to 4800 EUR for connecting the gutters and sewage to the sewer system. The first point that makes me suspicious is that connecting one or two pipes is as expensive as the entire excavation and filling. That seems overpriced to me and secondly, these costs were never discussed with us. They are necessary, but perhaps we would have wanted to have this done elsewhere. You cannot provide a service for 4800 EUR without consultation without us giving an order or even agreeing to it verbally.

Who is right here?

To take a shot in the dark: There are costs that the municipality charges you. And especially the sewer connection is sometimes incredibly expensive, and definitely a point where the prices are not always comprehensible. But it doesn’t help – for these costs you have probably already submitted a 'Kostenübernahmeerklärung' with the building application.

We know from a neighbor that this is not commissioned directly by the municipality. He awarded it elsewhere at the time. We know the costs that will still come from the municipality and have them saved up. Electricity, gas, development, water, telecom, there are cost estimates for everything, you have to at least say beforehand that there will be costs X :-/

At €5000 for the earthworks, I am not surprised at all that there are still invoices coming in. That seems to be a standard figure to reassure the customer. I think €10,000 is a realistic amount.

Hello,

Who is right here?

Who is supposed to be able to answer that seriously without knowledge of your contracts?

Rhenish greetings

To my knowledge, only the "general contractors" commissioned by the municipality are allowed to connect to the public sewer system itself. In our case, our company did everything except the connection – a separate company came specifically for that, set the connection, and then left. We paid extra for that. Our company was not allowed to connect to the public network – although they could have done it. The costs were clear to us in advance because our earthworks contractor pointed out these additional items to us.