Centurion Farms Ltd. v. Citifinancial Canada Inc., 2013 ONCA 79 has a helpful statement of the test for improvident sale by a mortgagee of a mortgages property:
 ... the proper test is whether a mortgagee has taken reasonable precautions to obtain the true market value of the property as of the date of the sale. See Oak Orchard Developments Ltd. v. Isenan  O.J. No. 361 (Ont. H.C.) aff'd  O.J. No. 2334 (Ont. C.A.)... .