99b----------------------------------------99b

1) A SHALI'ACH WHO SELLS A FIELD TO MORE THAN ONE PERSON
QUESTION: The Gemara earlier (99a) discusses a case of a landowner who sends a Shali'ach to sell a "Kur" of his land, and the Shali'ach sells it in two installments, half a "Kur" at a time. In such a case, has the Shali'ach violated his mission (since the owner does not want to have so many Shtaros to deal with) and the sale is not valid, or is his action considered acceptable to the sender? The Gemara there does not reach a conclusion.
The Gemara here asks another question in what seems to be a new Sugya altogether. The Gemara states that when a landowner tells a Shali'ach to sell a field "to one person but not to two," it is clear that if the Shali'ach sells it to two the sale is invalid. The Gemara asks whether the sale is valid or not in a case in which the landowner tells a Shali'ach to sell a field "to one person" and he does not specifically state "but not to two." The Gemara cites a Machlokes among Amora'im whether the sale is valid or not when the Shali'ach sold the field to more than one person. The Gemara concludes that the Shali'ach may sell the field to as many people as he wants and the sale is valid.
Why does the Gemara here ask whether the Shali'ach may sell the field to more than one person? The answer to this question should depend on the answer to the Gemara's previous question. If a landowner does not want his Shali'ach to sell his field in two parts so that he not have so many Shtaros to deal with, for the same reason he does not want the Shali'ach to sell the field to more than one person! The previous question was left unresolved, but now, when the Gemara asks the same question again, a number of Amora'im express their opinions on the matter!
ANSWERS:
(a) TOSFOS (DH Amar) explains in the name of RAV HAI GA'ON that the second Gemara is actually a continuation of the first. It is as if the Gemara is saying, "Now that we have shown that no proof can be found in a Mishnah or Beraisa to resolve the question, what did the Amora'im rule in the matter based on their own logic?"
This answer is slightly problematic. Why does the Gemara later cite a proof from the Mishnah here that the Shali'ach may sell the field to more than one buyer? The Gemara earlier cites the same proof and refutes it (in the same way the Gemara here will soon refute it). If this Sugya is a continuation of the previous Sugya, there is no reason to repeat the proof (and the refutation).
(b) Rashi seems to explain the Gemara in a manner similar to that of Rav Hai Ga'on, except that he explains that the first question of the Gemara involves a case in which the landowner says to his Shali'ach, "Sell a Kur of the land," and he does not specify that he should sell it to only one person. Although the question was not resolved, the Gemara assumes that the Shali'ach may sell the land to two people.
Now the Gemara asks what the Halachah is when the owner specifies to the Shali'ach that he should sell it to one person. Should the owner's specific instructions be interpreted to mean that he has an interest not to sell it to two people and not have too many Shtaros, or is he still not particular about how many people buy the land?
The Gemara cites proof again from the Mishnah to answer its second question. Although in the case of the Mishnah the Yesomim did not explicitly say that the land should be sold to only one person, nevertheless since Beis Din is mindful for the benefit of the Yesomim, if it is commonly considered beneficial not to have too many Shtaros it is as if they specified to sell it to one person. (Rav Hai Ga'on did not give this explanation because according to his Girsa, in the case of the second question the owner did not specify to sell the field to one person, but rather he told the Shali'ach to sell it and he did not specify to how many people.)
(c) The BA'AL HA'ME'OR also explains that the second question of the Gemara is like an "Im Timtzi Lomar" to the first question. The Gemara is assuming -- with regard to the first question -- that a person normally does not care if his field is sold to one person in two separate purchases with two separate Shtaros. He is not concerned with the fact that when there are more Shtaros more people will hear that he is selling his fields (which will cause the price of his fields to fall). Nevertheless, the Gemara considers that perhaps the same seller does care if his land is sold to two different people, because that raises a new consideration. When the land is sold to two people, the original owner will have to deal with two different court cases if the buyers find problems with the fields (for example, if the creditors of the seller expropriate the fields from them).
(d) TOSFOS, the RAMBAN (in Milchamos), and other Rishonim explain that the two questions of the Gemara need not be related at all. The first question of the Gemara, as the Ba'al ha'Me'or explains, refers to where the field is sold to one person in two different purchases and with two different Shtaros. The second question of the Gemara is not concerned with the extra Shtaros at all, but only with the fact that the field was sold to two people, and therefore the seller is concerned that he will have to be brought to court twice.
If the field is sold to two people, why is there not the additional concern that the seller prefers to avoid multiple Shtaros? The answer is either that both sales are written in a single Shtar (Tosfos), or that the problem with having two Shtaros is not that it will become publicly known that he is selling his fields, but simply that the he is lazy and does not want to have to find a scribe and witnesses to write a second Shtar. This is only a consideration when the Shali'ach who sells the field promises to the buyer that the seller (and not the Shali'ach) will write him a Shtar, in which case the seller is the one who must find the scribe and witnesses for the additional Shtar. The Gemara in its second question is not concerned about the presence of the second Shtar because it is discussing a case in which the Shali'ach writes the Shtaros himself, and thus the seller does not have to trouble himself with writing more Shtaros (Rabeinu Tam cited by Tosfos).
2) AN ERROR OF BEIS DIN IN APPRAISING THE VALUE OF A FIELD
QUESTION: The Mishnah states that if Beis Din errs when appraising the value of the property of Yesomim in order to sell it, the sale is revoked if the error is greater than one sixth of the value of the property (this refers to an "external" sixth, or twenty percent). This is a stringency unique to Beis Din. Normally, when a seller who sells Metaltelin overcharges by a sixth, or when a buyer underpays by a sixth, the sale is not revoked; rather, the seller (or buyer) must return the extra money. When a person sells land, even if he overcharges by more than a sixth the sale remains valid and is not revoked (and no money needs to be returned) because of the rule that "Ein Ona'ah l'Karka'os" ("there is no Ona'ah for land"). Although the Mishnah discusses the sale of land, since the property is being evaluated by Beis Din for the benefit of the Yesomim, the Chachamim were more stringent and decreed that the sale should be revoked if Beis Din under-appraises and undersells the land by a sixth of its value.
However, the Mishnah also says that if Beis Din overprices the land and the Yesomim profit more than a sixth, the sale is revoked! Why is the sale revoked if the Yesomim benefit from the error of Beis Din?
ANSWERS:
(a) The ROSH, RAN, and other Rishonim explain that since the Chachamim decreed that when Beis Din under-evaluates the land of Yesomim the sale is revoked, they made a reciprocal rule that if Beis Din overprices the land the sale also is revoked. Without such a reciprocal rule, no one would buy the property of Yesomim -- the downside to the buyer would be too great (that is, the sale might be revoked if Beis Din under-evaluated the land, but the sale would remain valid if Beis Din overpriced the land).
The Rosh suggests that this is the view of RASHI, and the Ran cites this view in the name of TOSFOS.
(b) The ROSH in the name of RABEINU YONAH and the RA'AVAD (Hilchos Mechirah 13:9) writes that since it is Beis Din that appraises the land, the buyer relies on Beis Din to make a proper appraisal. He trusts Beis Din's appraisal and does not make his own independent appraisal of the land's value. Therefore, if Beis Din overprices the land, Beis Din causes the buyer to lose, and therefore the Chachamim instituted that the sale is revoked in such a case as well.
One difference between these two approaches might be according to the opinion that a Shali'ach who sells the property of Yesomim has the same status as Beis Din who sells the property of Yesomim (100a, according to Rashi's explanation of the Gemara). According to the first approach above, when the Shali'ach overestimates the value of the field and overcharges the buyer, the sale should be revoked just as when he undercharges. According to the second approach, since it is the Shali'ach who makes the appraisal and not Beis Din (or the Shali'ach of Beis Din), the buyer does not trust the Shali'ach's appraisal and he makes his own independent appraisal, and thus if he overpays the sale should not be revoked.
(c) The RAMBAN explains that when the Mishnah says that when Beis Din overpriced the field the sale is revoked, the Mishnah does not refer to a case in which Beis Din sold the field of Yesomim in order to raise money to pay their debts. Rather, the Mishnah refers to a case in which Beis Din attempted to sell the fields of the Yesomim but was unsuccessful, and therefore Beis Din told the creditor himself that he must accept the fields as repayment of the debt for the value that Beis Din attributes to the fields. Since the creditor who receives the fields has no choice in the matter and must accept the fields at the value determined by Beis Din, if Beis Din mistakenly overprices the field the transfer of the property is revoked.
The RAN questions this explanation. If this is the intention of the Mishnah, why does the Mishnah conclude that if Beis Din makes an "Igeres Bikores" -- they announce that people should come and visit the field -- then even if they overprice or underprice the field the sale is valid? What difference does it make to the creditor if people visited the field and saw it? Beis Din still decided on the price, and if Beis Din's price was exaggerated, the transfer of property should be revoked!
The Ramban must mean that if Beis Din had people visit the field, this indicates that Beis Din's appraisal was accurate. Even if it now seems inaccurate, that is due to some external factor which causes the value to seem higher or lower, but at the time of Beis Din's appraisal the value they ascribed to the field was accurate. (M. Kornfeld)