I'm not a lawyer. I'm writing here to give you first support and I hope someone with proper knowledge will help you. Please do not take this answer as final.

First, during my living in the Netherlands, I found that Dutch are operating a lot with common sense. The law is trying to protect the weakest party, which in this situation you are. 

I don't know you personally, so I treat you from what I read. I also treat agency based the on text from the previous topic. As for me, they don't play well.

Yes, you had a verbal agreement but I think for such types of contracts Dutch law prefers the written and signed contract. I don't have details of your verbal communication, but it sounds reasonable that you decided to stop with it as you got all details of the contract. I also found a [link][1] which gives me hope that I'm right.

If you're not sure then pay 200 euro for a layer and get the proper answer. Ironic that I do remember that you wanted to save them.

In the worst case, you can sign and live in the apartment no longer than notice period in the contract.

  [1]: https://www.amsadvocaten.com/blog/contract-law/how-to-conclude-a-legally-binding-contract-in-the-netherlands/