Developer changes plot size

Do you want to get out of the contract, or do you just want to know if he can do that? If there are no alternatives anyway (plots, existing property, etc.), then this is the only alternative that remains, right? A four-family house does not necessarily have to be bad. If the development plan allows it, you can't prevent it anyway; even if the developer had built a bungalow, the later owner could have demolished it and built a multi-family house.

No, fortunately we do not have a price escalation clause in the contract. We do not want to get out of the contract. Surely he is waiting to sell everything and then start building. :-(
Thank you very much for your help. We will arrange an appointment and then report on it.