I do not know the link.
The semi-detached house is being built by a developer at a fixed price. The construction description lists builder-side services
But I assume that it is not a developer, but a general contractor!
In this respect, you will become the builder with a contract for work and services and will then also be responsible for all incidental costs incurred on the builder's side.
Anything else would be illogical.
The real estate agent mediates the plot of land as a separate contract. This could also be a linked transaction, which others here are more familiar with than I am.
By the way: you registered today and have just given your OK that you will not use links.
You can also use the exposé ID number here or use other terms that can serve for searching.