Is there an implied term in Ex. 1 of the Contractor's Statement of Claim?

The defendant in answer says that the documentation finally submitted was "usual" or the "custom of the trade" in this type of transaction. I consider this as an argument that there was an implied term in Ex. 1 that whatever documents, terms and conditions to be considered necessary and proper by the defendant's solicitor were to be accepted by the plaintiff. The plaintiff was inexperienced in this type of transaction. Although he had looked at other properties and had made an offer on another property, yet there is no history on his part that would suggest any such implied term. Consensus ad idem is essential to the creation of a contract and I feel it would be imperative that the defendant show clearly that what he tried to incorporate into the contract as implied is either in accordance with the consensus of the parties or implied by law and not negatived by the contract. To do otherwise would be to allow one party unilaterally to incorporate terms into the contract on the basis of what is "usual" or "the custom of the trade" from his subjective point of view. As stated by Falconbridge C.J.K.B. in Campbell v. Mahler (1918), 43 O.L.R. 395 at 398: "It is very seldom that there is any satisfactory evidence in this country of custom of trade. Generally, when a witness speaks of custom of trade, he really means to speak of a practice which he follows, and endeavours to get other people to follow, in his business."