827. Not Benefitting from Chometz

117:8 On erev Pesach, from the time when it becomes forbidden to derive any benefit from chometz, and on the rest of Pesach, a Jew may not even benefit from the chometz of a non-Jew. Therefore, it is prohibited for a Jew to transport or to watch the chometz of a non-Jew (even for free, because then the non-Jew will owe him a favor - see Mishnah Brurah 450:23). It is all the moreso prohibited to purchase chometz for a non-Jew, even using the non-Jew's money. (If one violated and did purchase chometz for a non-Jew on Pesach, the chometz may be permitted to Jews after Pesach so long as the Jew did not acquire it for himself and did not assume responsibility for it - MB 450:22.)

117:9 It is likewise prohibited to rent to a non-Jew an animal to transport chometz or a room to store chometz. This is because one may not earn money from things that are prohibited for benefit. It is permitted, however, to rent a non-Jew an animal for the week of Pesach - excepting Shabbos and yom tov - without any conditions so long as the non-Jew has not specifically indicated that he needs it to transport chometz. This is true even though the Jew knows that the non-Jew will transport chometz on it. In this case, however, that detail is not considered relevant because even if the non-Jew doesn't transport anything on it, he still needs to pay the rental fee. Therefore, the Jew is not actually earning anything by benefitting from chometz. Similarly, the Jew may rent the non-Jew a room to live in during Pesach even though he knows that he will bring chometz into it. The Jew is not collecting rent for the non-Jew to bring in chometz, just for renting the room. Again, this is because even if the non-Jew does not end up bringing in any chometz, the rent will not be affected.