Rav Chama brings 4 halachot – 3 relating to whether people have the right to make others living next door/on top of them tear down walls, houses, etc. to make their living space better. The third relates to concern over people taking advantage of orphans and forging documents to get out of repaying a loan. For what things can we force members of a courtyard to share costs for? Do residents of the town need to share the costs for a wall to protect the city and a door and lock? Do all the residents need to partake in an equal manner or do the wealthy need to pay more or do the ones living closer to the wall need to pay more as they need the protection more? Do talmidei chachamim need to pay at all because they are considered protected from God? 2 different verses are brought to show that they do not need protection. However Rabbi Yehuda Nesia insisted the talmidei chachamim pay.