688.1. Subject to the right of retention provided by article 689, no person may be declared purchaser if he does not immediately pay to the officer conducting the sale the amount described in paragraph e of article 670, either in cash or by certified cheque.
Failing payment, the officer cancels the adjudication and, according to the circumstances, continues the bidding or terminates the sale; if he terminates the sale, he inserts another notice in accordance with articles 670 and 671, at the cost of the person in default.
If the immovable is sold for a lower price than that bid by the person in default, he is liable to payment of the difference.