New sewage treatment plant, who pays the fees?

Hello everyone,
We are in the process of buying a house. Now the agent explained to me quite late, after we were almost in agreement, on the phone that he wanted to "fairly" point out to me that the municipality is currently building a new sewage treatment plant and that in probably about 2 years a bill will arrive at the house. He says that it is legally clearly regulated that we, as the new owners, have to pay this bill. He just wants to say it now so that there won't be any disputes later. In the notarized contract there is a sentence that no current bills are outstanding or something similar, but that does not concern the sewage treatment plant, even though it is already under construction.
I think he is right; that sounds logical to me, but I am not an expert. Do I have to watch out for anything?
Regards,
Tobi

He just wants to say it now so that there won't be any disputes later. In the notarized contract, there is a sentence stating that no current invoices are outstanding or something similar, but that does not apply to the sewage treatment plant, even if it is already under construction. I think he is right, that sounds logical to me, but I am not an expert. Do I need to watch out for anything?

Yes, that you now have a reason to negotiate the purchase price down. How much is the plant supposed to cost you? If suddenly €20,000 are coming your way, I would definitely start thinking about it.

Are the costs roughly known? Something like that also gets into the press. In our district town, major measures are announced, and you can always add 100% on top of that. The question is what awaits you? A one-time payment? An increase in wastewater fees? I would deduct that from the purchase price.

Yes, now you have a reason to lower the purchase price. How much is the system supposed to cost you? If suddenly €20,000 are coming at you, I would start to think about it.

Of course, I've already thought about that. According to his statement, about 2000 to 3000 euros are incurred. Of course, I am asking the municipality if that is correct.

Do you think you can trust the realtor if he tells you so late that something else is coming?

Ask the city and/or neighbors. If it's really only €3000, I would personally just accept it.

Then also take a look in the [Gemeindeverordnung] to see if you will be involved in the road construction. That can get really annoying. Municipalities with such citizen participation are suspicious to me.