Hekser micva / Szuká

A Jew who lights the candle from the fire of a non-Jew does not (say a) blessing over it at the close of Yom Kippur even though at the end of the Sabbath we do bless it, because we do not say a blessing over the fire on the close of Yom Kippur, only over light which was not burning during the daytime of Yom Kippur, or over the light that was lighted from it, and (therefore) the custom is to light from the lamps of the synagogue; however if one lighted (his candle) on Yom Kippur, if it was lighted with permission (i.e., if he was allowed to light it), for example for a sick person, we are able to say a blessing over it.
Hagah: There are those who say that one is to say the Prayer of Havdalah over the light of the synagogue, (המגיד ואבודרהם וא״ז), and there are those who say that one should not use (the light of the synagogue) for Havdalah, rather one lights another light from the synagogue lamp. The correct practice is to say the Havdalah over both of them together, that is to kindle one light from the light of the synagogue, but one should not make the Havdalah over the light of the synagogue alone, (מהרי״ל). For the rest of the laws concerning the light, see above in chapter 298. We eat and we rejoice at the close of Yom Kippur because it is somewhat of a holiday, (טור ומהרי״ו, א״ז). There are those who are strict and observe two days of Yom Kippur, and a person can be (halakhically) relieved of this practice, and one should not follow this strict practice since there is a fear that a person might be in danger (of his life or health), (א״ז). He who fasts because he had a bad dream on the day after Yom Kippur, there is no need for him to fast all his days (after Yom Kippur every year just because he did it once), (מנהגים) One does not say prayers of supplication nor does he say “You are righteous, and you will be righteous, and you were righteous” from Yom Kippur until Sukkot (the Festival of the Booths), and the meticulous ones begin immediately at the close of Yom Kippur to build the Succah so they can go from one commandment to another commandment, (מהרי״ל ומנהגים, והגהות מיימוני פרק ב‘ דברכות, מהרי״ו).

On Succot we shall dwell for 7 days etc. Because on Succot I protected the children of Israel. These refer to the clouds of glory who protected them from all the intense heat and the sun of the desert. And it is a Mitzvah to begin building the Succah immediately after Yom Kippur. For if a Mitzvah that comes to one's hands, one should not delay performing it.[Maharil]

1. The Blessing Shehecheyanu is Not Recited over the Construction of a Sukkah: One who constructs a sukkah, whether for himself or for someone else, does not make a blessing upon its construction. Shehecheyanu is appropriate to be said when one constructs a sukkah for himself. However, we rely on the blessing Shehecheyanu that we recite during Kiddush on the [first] night of Yom-Tov that [is recited] because of the mitzvah of sanctifying the festival, which is also a mitzvah that comes [only] periodically. (The one blessing covers both requirements).RAMA: If one does not eat in the sukkah on the first night, even though he sanctifies the festival in his house, when he does eat in the sukkah he must sanctify the festival due to the sukkah. If he sanctifies the festival at the time of construction of the sukkah, it is sufficient for him [R"an].

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One must pursue beautification of the mitzvah when buying an etrog: If one bought an etrog that can just barely fulfill the obligation, i.e. if it was exactly an egg-size, and afterward found a bigger one, it is a mitzvah to pay up to a third more than the price of the first to swap it out for the nicer one. There is one who says that if there are two etrogs available for purchase, one nicer than the other, the nicer one should be purchased if it is not more than a third more expensive than the other one. RAMA: Somebody who doesn't have an etrog or some other [objected associated with a] mitzvah whose time will elapse need not dispense much wealth on it, as they said, "One who dispenses [money to charity] should not dispense more than one-fifth [of their wealth]" [Ketubot 50a], even with respect to a mitzvah with a time that will elapse (Ros"h, Rabbeinu Yerucham 13:2). This specifically applies to a positive mitzvah. However, regarding a negative mitzvah, one should spend all of their wealth rather than sin (Rashb"a and Raavad). See the end of 658 in the Rama.

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He who makes a sukkah for himself, says: “He Who sanctified us by His commandments and commanded us to make a sukkah.” For others: “to make a sukkah in that one’s name.” If he enters it, he says: “Praise to Him Who sanctified us by His commandments and commanded us to dwell in a sukkah.” After he recited the benediction in the first night of the holiday he does not have to recite it again. He who makes a lulav for himself, says: “He Who sanctified us by His commandments and commanded us to make a lulav.” For others: “to make a lulav in that one’s name.” If he uses it, he says: “Praise to Him Who sanctified us by His commandments and commanded us to take a lulav,” and “He Who let us live.” He recites the benediction every time that he takes it.

And despite the fact that phylacteries written by a gentile are unfit, a Jew who writes them does not have to recite a blessing. As Rav Ḥiyya, son of Rav Huna, sent a ruling in the name of Rabbi Yoḥanan: On phylacteries of the arm one says the blessing: Blessed are You, Lord our God, King of the universe, Who has sanctified us through His mitzvot and commanded us to don phylacteries. On phylacteries of the head one says the blessing: Blessed are You, Lord our God, King of the universe, Who has sanctified us through His mitzvot and commanded us concerning the mitzva of phylacteries. The implication of this is that one recites blessings only when he dons the phylacteries, whereas when he writes the phylacteries he does not recite a blessing: To prepare phylacteries.

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It is taught in another baraita that Rabbi Eliezer says: Just as a person does not fulfill his obligation on the first day of the Festival with the lulav of another, as it is written: “And you shall take for yourselves on the first day the fruit of a beautiful tree, branches of a date palm” (Leviticus 23:40), and the Sages derive from the phrase: Shall take for yourselves, that it must be taken from your own and not from that of someone else, so too, a person does not fulfill his obligation with the sukka of another, as it is written: “You shall prepare for yourself the festival of Sukkot for seven days” (Deuteronomy 16:13), and the Sages derive from the term “for yourself” that it must be taken from your own.