I guess you usually commit to paying for the house and then pay a downpayment that is non-refundable if you then cannot pay for the house. This way the money wi

I guess you usually commit to paying for the house and then pay a downpayment that is non-refundable if you then cannot pay for the house. This way the money will be a safety net for the builder, since he could have found a different buyer during the time that the house will be empty.