Dovid Grossman was told by R’ Zalman Nechamia Goldberg that although it is preferable, per the Rambam, to make a kinyan sudar when appointing a shaliach, if it is difficult it is not required.
A Teshuva from
Dayan Yehoshua Grunwald
March 4, 2021
Contemporary poskim permit a person to appoint a rav to sell his chametz over the phone. (See Mechiras Chametz Kehilchaso 17:11.) This verbal communication is sufficient to make the rav his shaliach (proxy) to sell the chametz. Since the seller is not selling the chametz directly to the rav, no formal kinyan is absolutely required. The rav can write down the details of the chametz—value, location, etc.—as they were reported to him.
One concern with phone authorization is that since no shtar harsha’ah (authorization) is signed, there is no proof of the rav’s appointment, which could possibly invalidate the sale. A remedy would be to additionally sign a shtar harsha’ah and send it to the rav by email or otherwise..
The Chasam Sofer (Shu”t, Even Ha’ezer 1:43) allows authorization of the rav by mail. Doing so online or by email, text message, or the like would seem no different. An electronic communication that leaves a record is superior to a phone call.
Another concern with phone or online appointment of the rav as a shaliach is the absence of the kinyan sudar. Some have suggested that a kinyan sudar be made between the seller and a third party. R’ Dovid Grossman was told by R’ Zalman Nechamia Goldberg that although it is preferable, per the Rambam, to make a kinyan sudar when appointing a shaliach, if it is difficult it is not required.
https://baishavaad.org/qa-from-the-bais-havaad-halacha-hotline-33/
