Actually quite a few years as LL(blush), but other tenants are n

1,不續就不續,又不是求他.

    You are right. They are troublemaker. Told them to move out by the lease end if not satisfied with the solution (they replace the filter, we cacuum clean the vents)

2,有狗不說能罰款嗎?看看當初怎麽寫的? Tried not to upset them in case they make more mess before the moveout.

３，應該是他們自己換ｆｉｌｔｅｒ吧？ Yes. Asked them to.

４，他們不換，事後還是你自己清掃一下，但就不給他們做．Yes. Told them will vacuum clean the vent. If still not satisfied, they can move.

Thank you. Will update.