What is the test for determining that the borrowing cost in a mortgage transaction is excessive?

In Wetter v. Nasgowitz (1983), 1973 CanLII 1307 (SCC), 54 D.L.R. (3d) 766, this court was concerned with an appeal from the decision of a trial judge that the cost of borrowing in a mortgage transaction was excessive and that the transaction was harsh and unconscionable within the meaning of those terms in the Consumer Protection Act. McFarlane J.A., delivering the judgment of the court, said at p. 767: In my opinion, the respondents in this case have failed to establish by evidence that the borrowing cost is excessive. Indeed, the only evidence to which we have been referred relating to that specific and important question was that it was not excessive, that evidence came in the form of testimony by witnesses having knowledge of the money market who said that they were of the opinion that the respondents could not have borrowed the money they wanted when they wanted it at any better terms than are those disclosed in the evidence. That being so, I think that, with great respect to the trial Judge, the evidence in this case did not justify or support his finding on the first and vital requirement of the statute, namely, that the cost of borrowing is excessive having regard to the risk and all of the circumstances. That, in my opinion, is sufficient to dispose of this case.