וְכָל־עֶרְכְּךָ֔ יִהְיֶ֖ה בְּשֶׁ֣קֶל הַקֹּ֑דֶשׁ עֶשְׂרִ֥ים גֵּרָ֖ה יִהְיֶ֥ה הַשָּֽׁקֶל׃ (ס)
你所定的一切估價，都要按照聖所的舍客勒計算；二十季拉為一舍客勒。
Rashi
וכל ערכך יהיה בשקל הקדש Every valuation shall be made according to the holy shekel: i.e., every valuation regarding which shekels are written, will be made according to the holy shekel.
Siftei Chakhamim
Must be in holy shekolim. Rashi is answering the question: The verse implies that no valuation is less than a shekel, but this is not true since we assess him according to his means and leave him enough to live on, as said earlier (verse 8).
Rav Hirsch
V. 25. וכל ערכך וגו׳. Nur durch Geld oder Geldeswert werden הקדשות ausgelöst, nicht aber durch עבדים שטרות וקרקעות (Bechorot 51a-b). Nur mobile (nicht קרקעות und ihnen gleichgeachtete עבדים) und wirkliche Güter (nicht שטרות) erscheinen lediglich als Wertobjekte für den Tauschzweck.
Rashi
עשרים גרה TWENTY GERAH — twenty meahs. This was what it was originally, but later on they increased it by one sixth. Our Rabbis stated: six silver meahs make a silver denar; thus twenty-four meahs make a selah (a shekel) (cf. Rashi on Exodus 30:13), a shekel being four denars (Bekhorot 26b).