What are the implications of "ve'Kam ha'Bayis ... la'Tzemisus"?
Rashi: It means that, when Yovel arrives, the permanent rights that that the owner had in the house, now go over to the purchaser, and the field becomes his forever.
What is the significance of the fact that the word "Lo" is spelt with an 'Alef' and pronounced with a 'Vav'?
Rashi: It teaches us that, even if the town is not currently surrounded by a wall, it is considered a walled town if it had a wall around it in the time of Yehoshua ben Nun. 1
As if to say, 'It doesn't have a wall, but it did'. Rashi: The Torah ought really to have written "Lah" (with a 'Hey'), seeing as "Ir" is feminine, and it wrote "Lo" with a 'Vav', because it has the same sound as "Lo" with an 'Alef'.
Why does the Torah add "Lo Yeitzei ba'Yovel", which is seemingly superfluous?
Rashi (citing Rav Safra): To teach us that even if Yovel occurs during the first year, the house does not revert to the owner.