Selling Houses in Walled Israeli Cities

Walled Cities

Whether their sanctity was maintained when the Jews returned from Bavel for the Second Temple: Megillah 10a-b

A city for which the walls were destroyed: Megillah 10b

Whether the year consists of 354 days or 12 months: Rosh HaShanah 6b

How the year is calculated, in leap years: Rosh HaShanah 6b

Kohanim and Levites can always renege: Rosh HaShanah 29a

Whether houses of less than 4*4 Cubits fall under these rules: Succah 3a-b

Source for an obligation for relatives to buy it back: Kiddushin 21a-b

Whether he can buy back half of the amount at one point: Kiddushin 20b-21a

Whether one must borrow money in order to buy back the house: Kiddushin 20b-21a

Whether relatives of the seller can force the buyer to sell it to them: Kiddushin 21a