VEFA buying

Hello.

I'm Belgian and I consider to buy a VEFA apartment.

For what I see, the sector is not bright at the moment with sole bankrupts and a lot of delays.

Is it usual/possible to negotiate the price? Can we directly contact the promoter (Thomas & Piron) instead of the real estate agents?

Do we have some sort of insurance or compensation about the potential delay?

Other question: are the notaries free of charge when we just want to ask them for some advices? (this is the case in Belgium)

Any recommendations of notaries?

Thank you 🙏