False statement by sales partner at developer

Is there a clause about collateral agreements in the purchase contract?

It might help, but apparently there is no way around a lawyer.

In the chapter "Notes" there is the following passage: "Unnotarized agreements are invalid and can lead to the nullity of the entire contract (§311 b para. 1 Building Code)".

Distribution partner sounds to me like someone who is not employed by the property developer and thus acts as a third party who has no direct influence on the contractual relationship between buyer and property developer.
Is that the case? "Independent commercial agent" or sales employee employed by the PD?

So yes, definitely an independent company. They were and are commissioned exclusively for the property developer. In addition, the sales employee responsible for us appeared at the notary appointment as an unauthorized representative for the property developer.

The satellite dish costs 500-1000€ including installation. Then it is technically 'free' but the picture quality is catastrophic. So another 60€ per year for an HD card is gone. I would give up on everything and handle everything over the internet connection. For the 1000€, I would rather plan for 5-6 extra LAN sockets. There are plenty of providers nowadays and the variety is just as big. I think they couldn't distinguish between DSL and cable. Hence the wrong information.

Catastrophic is really an exaggeration. Sure, private channels are not available in HD without [HD+]. But if you watch little TV, that shouldn't bother you. Otherwise, you pay the money to Telekom ([MagentaTV]) or providers like Zattoo. So it doesn't matter.

The satellite dish including installation costs 500-1000€. Then it's technically 'free' but the picture quality is terrible. So that's another 60€ annually for an HD card. I would forgo everything and handle everything via the internet connection. For the 1000€ you’d rather budget another 5-6 extra LAN outlets.
There are plenty of providers nowadays and the variety is just as big. I think he couldn't distinguish between DSL and cable. Hence the wrong info

I just checked again. Catastrophe looks different^^

back to topic, have you spoken directly with the property developer? It's probably not the only unclear item.

Stable 50mbit are more than enough for TV streaming via DSL - with us even via WLAN. It is now super comfortable, I wouldn’t want anything else anymore. There are also good prices available nowadays.

I would inquire about the case with the sales partner. Maybe you will get a discount/compensation. I think 500-1000€ for developer sales partners for a house is simple. You will then still have a good relationship with them.