Architect contract with developer - draft purchase agreement available

We intend to purchase a plot of land from a developer. The draft purchase contract is available. Before the notarial deed is signed, he requires the signature of an architect contract. How should one proceed here? Do you have any experience with this? Is there still a withdrawal period here?

It's only logical, you're not just buying the plot from a developer. How else would that work.

But first, the property or=

Well, it's a vicious circle, but he certainly won't sell you the property without a contract, so what reason would you have left to sign the contract with the developer.

Understood. But shouldn't such contracts actually be viewed together?

There may be other variants, we were once close to a deal with a developer, and it was exactly like that. However, the contract with the developer clearly stated which property belonged to it under what conditions.