On Motzaei Yom Kippur, after breaking his fast, Mr. Hadar went to buy a lulav and esrog.
His cousin, Mr. Green, sold arba minim, and for years Mr. Hadar had bought from him.
After examining many esrogim, Mr. Hadar found one that exceeded his expectations – almost perfectly clean, symmetrical shape, reasonably large, and yellow in color.
“This one looks great!” Mr. Hadar said to Mr. Green. “How much is it?”
“It’s one of my very best ones,” said Mr. Green. “I’m selling it for $500.”
Mr. Hadar took a deep breath. “That’s a lot more than I planned to spend,” he said.
“How much did you have in mind?” asked Mr. Green.
“About $200,” replied Mr. Hadar. “Tops, $250.”
Mr. Green thought for a moment. “Give me $250 now, and take the esrog,” he said. “Meanwhile, let me see how business goes during the week. We’re family – I’ll give you a good price!”
“Fair enough,” said Mr. Hadar. He paid the $250 and went on to choose a lulav, hadasim, and aravos.
On Succos morning, Mr. Hadar showed his esrog to an avreich who was knowledgeable about esrogim.
“That’s a beauty!” the avreich exclaimed. “It must have cost a pretty penny!”
“My cousin said he would give me a good price,” Mr. Hadar replied, “but we never finalized how much.”
“If you never finalized the price, I’m not sure the esrog is yours…” the avreich said thoughtfully. “You may not be able to use it, because you must own the esrog on the first day. You should ask Rabbi Dayan!”
Mr. Hadar quickly approached Rabbi Dayan and asked:
“Is there a problem using the esrog if we didn’t finalize the price?”
“The Gemara (B.B. 86a; Avodah Zarah 71b) teaches that if the price was not set – even if the buyer made a kinyan, such as physically taking the item – the acquisition is not complete,” replied Rabbi Dayan. “Without setting the price, the parties cannot have full intent (gemirus da’as), lest they disagree about the price, so that both parties can retract” (C.M 200:7).
Rambam (Hil. Mechira 4:11-12) indicates that even if they agree afterwards, the initial kinyan is not valid (Pischei Choshen, Kinyanim 1:5[8]). However, if the item has a known price, even if it was not explicitly stated, or if the parties initially agreed that the price would be established by a third party, the kinyan is valid (Sma 200:14).
Nonetheless, in the context of mechiras chometz or mechiras bechor, Maharsham (7:121) discusses whether the sale to the non-Jew can be valid if the price of the chometz or animal was not set beforehand nor, as is commonly done nowadays, subject to evaluation by a third party.
He cites from Tur Ha’even (#7) that if the buyer relies on the seller to set a fair price, the sale is valid, similar to when relying on a third party, but Radbaz (6:2282) disagrees. Maharsham adds that if the parties merely state that they will not argue, but do not specify who will rely on whom, even Tur Ha’even would agree that the transaction is not valid.
Tur Ha’even continues that regarding mechiras chometz or mechiras bechor, the sale is valid even without setting the actual price, because the seller clearly wants to uphold the sale to avoid the potential prohibition. He further posits that if the parties later agree on the price, the sale is valid retroactively, at least when there was partial payment. Maharsham seriously questions this.
Igros Moshe (C.M. 1:51) also suggests that when there is even partial payment, the sale is valid, because otherwise the money would become a loan. He further suggests that when there is a defined discrepancy, that would still be considered setting a price, but he remains in question about such a case.
“Thus, according to Tur Ha’even and Igros Moshe, the esrog is yours,” concluded Rabbi Dayan, “because you relied on Mr. Green, you paid partially, the price range was set, and the seller wants the sale to be valid, because the esrog will be almost worthless after Succos. In the future, though, you should finalize the price at the time of the sale.”
Verdict: Generally, a kinyan is not valid if the price is not set. Some poskim uphold the sale when one party relied on the other, there is at least partial payment, the price range is defined, and/or there is specific desire to uphold the sale.