Drainage plan in the contract as an additional service?

Hello dear community,

we recently went through the contract with our architect, the contract includes service phases 1-4 according to HOAI.
The drainage plan is listed as an additional service for a whopping €2500 extra. Is that normal?
Furthermore, he does not want to hand over the contract to us and insists that we read and sign the contract at his office.

What do you think about that?

I would basically not sign the contract if it is not provided to me beforehand. I need the contract so that I can also have peace in case there are different memories of what was agreed. Trust is the basis I need for my relationships. What does not start with trust, in my view, is on an unhealthy foundation. For construction, that would be way too risky for me.

The drainage plan had to be calculated externally for us because we have to let the water from the sealed surfaces seep away and are not allowed to discharge it. That is beyond the competence of the architect; we paid a similar amount for it.

The architect is a service provider for you and is also supposed to advise you later. If discrepancies arise before signing the contract, I would look for another contracting party. In our case, the drainage plan including the application was not part of the contract. It was executed and invoiced at 500 € net. It was paid by us without objections.