S sold to B a car for P1M. The condition for the sale is for B to execute a chattel mortgage on the thing sold. The balance of 800,000 is payable in twenty equal installments. B defaulted on his 2 or more installments so S foreclosed the mortgage and sold it for P700,000. Can S recover the deficiency? Give reason/s? Use article 1484 as a fact to support the claim.