在加拿大买房什么样的房屋买卖合同是有效的 很多人以为买卖双方签署了房屋买卖合同书后, 合同就是有效的, 其实不然. 在这里, 首先需要说明的是, 合同的合法性绝不是仅仅由一份合同书能决定的. 在加拿大, 有效的合同由以下5个基本要素决定: The parties entering into a contract must be legally competent to contract (capacity of the parties). The contractual arrangement must be lawful (lawful object or legality of object). Each party must receive something (consideration). There must be offer and acceptance (mutual agreement). Both parties must consent to the terms of the contract (genuine intention). The agreement must be certain (definite and clear).如果一份合同不满足以上任何一个基本要素, 此合同无效(Void), 或有可能成为无效的合同(Voidable): Void (never came into existence); Voidable (originally valid but capable of being rejected by the offended parties at a later time); or Illegal (not enforceable by the courts).