One must make sure his chometz is located in a clear spot in his house. Thus, in any room or cabinet that has chometz or possible chometz, one should mark that the area is sold to a non-Jew so that if the non-Jew were to come on Pesach to take his chometz, he would find it easily and not need to do a bedikas chometz...
Similarly, if one sells chometz that is in his car, he should indicate the license plate number and description of the car in the harsha’ah so that the non-Jew can find it easily.
If one includes a storage room in his sale, he should indicate exactly which door goes to his storage room. It is not enough to write “the chometz in the storage room on the storage level.” If it is hard to describe which door is his, he should put a note with a number on the door and write in the harsha’ah that he is selling the storage room with the number that is on the door.
If one has chometz or a chometz order on a ship’s cargo, he should write the order or delivery number so that the non-Jew has a way to track it. Similarly, if one owns chometz that is being held in storage by a company that sells goods online, e.g., Amazon, he must write the identifying details and numbers and ensure that he does not continue selling the chometz during Pesach online.
