Is a solicitor required to sign a letter of approval to complete the sale and purchase of a farm?

Counsel for the applicant argued that the following passage from Carruthers v. Whitaker, [1975] 2 N.Z.L.R. 667, at 671 is applicable: It is established by the evidence to which I have earlier referred that at the time when the parties instructed their respective solicitors, they all had in mind only one form of contract which would govern the sale and purchase of the farm, namely, a formal agreement in writing to be prepared and approved by the solicitors. When parties in negotiation for the sale and purchase of property act in this way, then the ordinary inference from their conduct is that they have in mind and intent to contract by a document which each would be required to sign. It is unreasonable to suppose that either party would contemplate that anything short of the signing of the document by both parties would bring finality to their negotiations. Furthermore, both parties would expect their solicitors to handle the transaction in a way which would give them proper protection from the legal point of view.