Update :

We had a phonecall from the people from whom we were going to buy a house yesterday. It was quite aggressive from the owner, saying we owed the 3000 francs. Luckily my husband was home to take the call. (But we guess they were ringing, because they knew they didn't really have a case) They said they'd done LOADS of work for us (well, three half hour meetings plus looking at a kitchen) My husband said: no you haven't!

Anyway, after a fairly heated argument, the owner realized they had made mistakes in the process and in pushing us to sign so quickly. And my husband agreed to compromise by paying half the notary fee (which is about 600f ) So, now we can rest in peace!!

Thanks to all who responded so helpfully

But my advice is BEWARE, in Switzerland. In my experience any service, you may have end up paying for!!