SAT system in new construction: Unicable or star wiring?

Exact Quad LNB with integrated multiSwitch and one connection per TV provides Sat to four devices, all four can receive different programs simultaneously. If they have built-in Sat tuners, which is the current state of the art, then no extra receivers and no extra FBD.

What is a realistic price for a satellite system in a new building with installation aimed at supplying two TVs with built-in receivers?

600-900 depending on the provider. Our electrician charged 600,- but that was cheap. Execution: dish aluminum, double LNB, three antenna sockets in the house, two in the living room and one in the guest room. Wall mount steel pipe hot-dip galvanized on the garage.

Our general contractor has set a flat rate of €1000 for the complete satellite system including mounting, roof tile, etc., cabling to all rooms (except bathroom, hallway....)

In my opinion, it's too expensive, but I can't do everything myself if you eventually want to move in (to a finished house). I've already taken on way too much anyway.

Yes, that's just how it is, either you do it yourself or have it done.

Nowadays, I would only install Sat over IP. And in EVERY room (including bathroom, hallway, kitchen) 2 LAN double sockets.