In what circumstances will a vendor be held to his contractual right to retain his purchase-money?

In Stockloser v. Johnson, supra, Romer L.J. stated at p. 501: There is, in my judgment, nothing inequitable per se in a vendor, whose conduct is not open to criticism in other respects, insisting upon his contractual right to retain instalments of purchase-money already paid. At p. 502 he stated further: It seems to me that in the long run it is much better that people who freely negotiate and conclude a contract of sale should be held to their “bargain” rather than that the judges should intervene by substituting, each according to his own individual sense of fairness, terms which are contrary to those which the parties have agreed upon for themselves.