问你的中介,一般屋主不敢随便违约
让你的中介干活
comission不是白拿的
The key point is...
The house is at first not eligible to be sold. So even you and the seller submitted the contract to HDB, the contract will be cancelled and void.
What you can do: The seller's agent is responsible for this you probably could sue the agent for mis-representation. Even your representing agent should be responsible for that. You can check with any property lawyers for the details. You can surely get back more than what you have paid to the seller.