Rashi: Pasuk 12 refers to somebody else who redeems the animal, who pays the value of the animal to Hekdesh, based on the Kohen's evaluation; Whereas Pasuk 13 is referring to the owner of the animal (who has the first right to redeem it, and) who is obligated to add a fifth. ^{1 2}

Sifra: To incorporate a woman and an heir in the Din of adding a fifth when redeeming their property from Hekdesh.