Halacha

הלכה א
אַרְבַּע מִדּוֹת בְּמוֹכְרין. מָכַר לוֹ חִטִּים יָפוֹת וְנִמְצְאוּ רָעוֹת הַלּוֹקֵחַ יָכוֹל לַחְזֹר בּוֹ וְלֹא הַמּוֹכֵר. רָעוֹת וְנִמְצְאוּ יָפוֹת הַמּוֹכֵר יָכוֹל לַחְזֹר בּוֹ וְלֹא הַלּוֹקֵחַ. רָעוֹת וְנִמְצְאוּ רָעוֹת יָפוֹת וְנִמְצְאוּ יָפוֹת אַף עַל פִּי שֶׁאֵינָן יָפוֹת שֶׁאֵין לְמַעְלָה מֵהֶן וְלֹא רָעוֹת שֶׁאֵין לְמַטָּה מֵהֶן וַהֲרֵי יֵשׁ שָׁם הוֹנָיָה שְׁתוּת אֵין אֶחָד מֵהֶם יָכוֹל לַחְזֹר בּוֹ אֶלָּא קָנָה וּמַחֲזִיר אוֹנָאָה:
כסף משנה
1.
There are four states applicable with regard to a seller:
a) The seller sold wheat assuring the purchaser that it was of a high quality, and it was discovered to be of a low quality. In such an instance, the purchaser may retract, but not the seller.
b) If the purchaser convinced the seller that the wheat was of a low quality, and it was discovered to be of a high quality. In such an instance, the seller may retract, but not the purchaser.
c-d) If the produce was said to be of a low quality, and it was discovered to be of a low quality, but not of the absolutely lowest quality, or he assured him that it was of a high quality, and it was discovered to be of a high quality, but not of the absolutely highest quality, we see if there was an unfair gain of one sixth of its value. If there was, neither may retract, but the unfair gain must be returned.

הלכה ב
אֲבָל הַמּוֹכֵר חִטִּים שַׁחְמָתִית וְנִמְצֵאת לְבָנָה. לְבָנָה וְנִמְצָא שַׁחְמָתִית. עֵצִים שֶׁל זַיִת וְנִמְצְאוּ שֶׁל שִׁקְמָה. שֶׁל שִׁקְמָה וְנִמְצְאוּ שֶׁל זַיִת. יַיִן וְנִמְצָא חֹמֶץ. חֹמֶץ וְנִמְצָא יַיִן. כָּל אֶחָד מֵהֶן יָכוֹל לַחְזֹר בּוֹ. שֶׁאֵין זֶה הַמִּין שֶׁאָמַר שֶׁיִּמְכֹּר לוֹ. וְכֵן כָּל כַּיּוֹצֵא בָּזֶה:
כסף משנה
2.
If, however, a person claims to be selling red wheat and in fact, it is white, white wheat and in fact, it is red, olive wood and in fact, it is from a wild fig tree, or wild fig wood and in fact, it is from an olive tree, wine and it is discovered to be vinegar, vinegar and it is discovered to be wine, both the seller and the purchaser can retract. For the object of the sale is not of the type that the seller stated he was selling. Similar principles apply in all analogous situations.

הלכה ג
הַמּוֹכֵר יַיִן לַחֲבֵרוֹ וּנְתָנוֹ הַלּוֹקֵחַ בְּקַנְקַנָּיו וְהֶחְמִיץ מִיָּד אֵינוֹ חַיָּב בְּאַחֲרָיוּתוֹ. וְאַף עַל פִּי שֶׁאָמַר לוֹ לְתַבְשִׁיל אֲנִי צָרִיךְ לוֹ. וְאִם יָדַע שֶׁיֵּינוֹ מַחְמִיץ הֲרֵי זֶה מִקַּח טָעוּת. מָכַר לוֹ יַיִן וַהֲרֵי הוּא בְּקַנְקַנָּיו שֶׁל מוֹכֵר וְהֶחְמִיץ. אִם אָמַר לוֹ לְמִקְפָּה אֲנִי צָרִיךְ וְהֶחְמִיץ מַחְזִיר וְאוֹמֵר לוֹ הֲרֵי יֵינְךָ וְקַנְקַנְּךָ שֶׁאֲנִי לֹא קָנִיתִי לִשְׁתּוֹתוֹ אֶלָּא לְבַשֵּׁל מְעַט מְעַט. וְאִם לֹא אָמַר לְמִקְפָּה הוּא אֵינוֹ יָכוֹל לְהַחְזִיר. שֶׁהֲרֵי אוֹמֵר לוֹ לָמָּה לֹא שָׁתִיתָ אוֹתוֹ. וְלֹא הָיָה לְךָ לַשְׁהוֹתוֹ עַד שֶׁיַּחְמִיץ:
כסף משנה
3.
When a person sells wine to a colleague and the purchaser transfers it to his own containers, even if it turns into vinegar immediately, the seller is not held responsible for it. This law applies even if the purchaser says: "I am purchasing it to use for cooking." If the seller knew that his wine was turning sour, the transaction is considered to have taken place under false pretenses.
Different laws apply if a person sold a colleague wine, and it remained in the seller's containers and turned into vinegar. If the purchaser told the seller: "I need this for cooking," and the wine turns sour, the purchaser may return it and say: "Here is your wine and your containers. I did not buy it to drink, but rather to use for cooking a little bit at a time."
If the purchaser did not say: "I need this for cooking," he may not return it. For the owner may tell him: "Why didn't you drink it immediately. You should not have left it until it turned sour."

הלכה ד
הַמּוֹכֵר חָבִית שֶׁל שֵׁכָר לַחֲבֵרוֹ וְהֶחָבִית שֶׁל מוֹכֵר וְהֶחְמִיצָה בְּתוֹךְ שְׁלֹשָׁה יָמִים הָרִאשׁוֹנִים. הֲרֵי זֶה בִּרְשׁוּת הַמּוֹכֵר וּמַחֲזִיר אֶת הַדָּמִים. מִכָּאן וְאֵילָךְ בִּרְשׁוּת הַלּוֹקֵחַ:
כסף משנה
4.
The following rules apply when a person sells a barrel of beer to a colleague in a barrel belonging to the seller. If the beer becomes like vinegar within the first three days [after the sale, the change is considered to have taken place in the seller's domain and he must return the money he received. From that point onward, the change is considered to have taken place in the purchaser's domain.

הלכה ה
הַמּוֹכֵר חָבִית שֶׁל יַיִן לַחֲבֵרוֹ כְּדֵי לְמָכְרָהּ מְעַט מְעַט וְהֶחְמִיצָה בְּמַחֲצִיתָהּ אוֹ בִּשְׁלִישָׁהּ חוֹזֶרֶת לַמּוֹכֵר. וְאִם שִׁנָּה הַלּוֹקֵחַ הַנֶּקֶב שֶׁלָּהּ אוֹ שֶׁהִגִּיעַ יוֹם הַשּׁוּק וְשָׁהָה וְלֹא מָכַר הֲרֵי הִיא בִּרְשׁוּת הַלּוֹקֵחַ. וְכֵן הַמְקַבֵּל חָבִית שֶׁל יַיִן מֵחֲבֵרוֹ כְּדֵי לְהוֹלִיכָהּ לְמָקוֹם פְּלוֹנִי לְמָכְרָהּ שָׁם וְקֹדֶם שֶׁהִגִּיעַ שָׁם הוּזַל הַיַּיִן אוֹ הֶחְמִיצָה הֲרֵי זֶה בִּרְשׁוּת הַמּוֹכֵר. מִפְּנֵי שֶׁהֶחָבִית וְהַיַּיִן שֶׁלּוֹ. וְכֵן כָּל כַּיּוֹצֵא בָּזֶה:
כסף משנה
5.
The following rules apply when a person sells a barrel of wine to a colleague who intends to sell it little by little. If half or a third of the wine becomes sour, it may be returned to the seller. If, however, the purchaser changes the hole for the spout, or the market day came and he was lax and did not try to sell the wine, it is considered to be in the purchaser's domain. Similar laws apply when a person accepts a barrel of wine from a colleague with the intent of transporting it to a particular destination and selling it there. If the price of the wine decreases or it becomes sour before it reaches the destination, it is considered to be in the purchaser's domain, for the barrel and the wine are his. Similar principles apply in all analogous situations.

הלכה ו
הָאוֹמֵר לַחֲבֵרוֹ יַיִן מְבֻשָּׂם אֲנִי מוֹכֵר לְךָ חַיָּב לְהַעֲמִיד לוֹ עַד עֲצֶרֶת. אָמַר לוֹ יַיִן יָשָׁן אֲנִי מוֹכֵר לְךָ נוֹתֵן לוֹ מִשֶּׁל שָׁנָה שֶׁעָבְרָה. מְיֻשָּׁן מִשֶּׁל שָׁלֹשׁ שָׁנִים. וְצָרִיךְ שֶׁיַּעֲמֹד וְלֹא יַחְמִיץ עַד הֶחָג. וּבְמָקוֹם שֶׁיֵּשׁ מִנְהָג יָדוּעַ הַכּל כְּמִנְהַג הַמְּדִינָה:
כסף משנה
6.
When a person tells a colleague: "I am selling you fragrant wine," he is responsible for the wine to retain its fragrance until the holiday of Shavuot. If he tells him: "I am selling you aged wine," he must give him wine from the previous year. If he mentions vintage wine, it must be in its third year and must retain its flavor without turning sour until the holiday of Sukkot.
In a locale where there is a well-known custom, everything is determined by the local custom.

הלכה ז
הָאוֹמֵר לַחֲבֵרוֹ מַרְתֵּף זֶה שֶׁל יַיִן אֲנִי מוֹכֵר לְךָ לְמִקְפָּה. אוֹ שֶׁמָּכַר לוֹ מַרְתֵּף שֶׁל יַיִן סְתָם. הֲרֵי הַלּוֹקֵחַ מְקַבֵּל עָלָיו עֲשָׂרָה קַנְקַנִּים בְּכָל מֵאָה שֶׁלֹּא יִהְיֶה יֵינָם טוֹב אֶלָּא כְּבָר הִתְחִיל לְהִשְׁתַּנּוֹת. יֶתֶר עַל זֶה לֹא יְקַבֵּל:
כסף משנה
7.
When a person tells a colleague: "I am selling you this cellar of wine for cooking," or merely "...a cellar of wine," the purchaser accepts the fact that the wine from ten containers out of one hundred will not be of as high a quality and will already have begun to sour. If more wine changes flavor, he has not acquiesced.

הלכה ח
אָמַר לוֹ מַרְתֵּף שֶׁל יַיִן אֲנִי מוֹכֵר לְךָ לְמִקְפָּה. אוֹ שֶׁאָמַר לוֹ חָבִית שֶׁל יַיִן אֲנִי מוֹכֵר לְךָ. נוֹתֵן לוֹ יַיִן שֶׁכֻּלּוֹ יָפֶה וְרָאוּי לְתַבְשִׁיל. אָמַר לוֹ מַרְתֵּף זֶה שֶׁל יַיִן נוֹתֵן לוֹ יַיִן הַנִּמְכָּר בַּחֲנוּת שֶׁהֲרֵי הוּא בֵּינוֹנִי לֹא רַע וְלֹא יָפֶה. אָמַר לוֹ מַרְתֵּף זֶה אֲנִי מוֹכֵר לְךָ וְלֹא הִזְכִּיר יַיִן אֲפִלּוּ כֻּלּוֹ חֹמֶץ הִגִּיעוֹ. וְכֵן כָּל כַּיּוֹצֵא בָּזֶה:
כסף משנה
8.
If the seller told the purchaser: "I am selling you a cellar of wine for cooking," or he told him: "I am selling you a barrel of wine," he must provide him with wine that is entirely of high quality and fit to be used for cooking. If he told him: "I am selling you this cellar of wine," he should provide him with wine similar to that sold in a store - i.e., of average quality, neither bad nor good. If he told him, "I am selling you this cellar," and did not mention that it contained wine, the purchaser must accept it, even if it was all vinegar. Similar principles apply in all analogous situations.

הלכה ט
הָאוֹמֵר לַחֲבֵרוֹ עֲרֵבָה שֶׁל עֵץ אֲנִי מוֹכֵר לְךָ. אוֹ קוֹרַת בֵּית הַבַּד אֲנִי מוֹכֵר לְךָ. אֵינוֹ נוֹתֵן לוֹ עֵץ שֶׁרָאוּי לַחְפֹּר בּוֹ עֲרֵבָה. אוֹ קוֹרָה שֶׁרָאוּי לִקְרוֹת בֵּית הַבַּד. אֶלָּא עֲרֵבָה בְּצוּרָתָהּ אוֹ קוֹרוֹת בֵּית הַבַּד בְּצוּרָתָם. שֶׁכָּל הָרוֹאֶה אוֹמֵר זוֹ עֲרֵבָה אוֹ זוֹ קוֹרַת בֵּית הַבַּד. וְכֵן כָּל כַּיּוֹצֵא בָּזֶה:
כסף משנה
9.
When a person tells a colleague: "I am selling you a wooden kneading tray," or "I am selling you a beam for an olive press," he may not give him a piece of wood that is fit to have a kneading tray hewn out from it, or a beam that is fit to be made into a beam for an olive press. Instead, he must give him a kneading tray that has already been fashioned or a beam for an olive press that has already been fashioned, one that any person seeing it will say: "This is a kneading tray," or "this is a beam for an olive press." Similar principles apply in all analogous situations.

קניין הלכות מכירה פרק יז
Kinyan Mechirah Chapter 17