Case: The plaintiff (=pl) had special benefits with a cellular phone company, enabling him to buy phones at 900 shekel a phone, or for free with the commitment to use their plan for 36 months. Pl did not need the phones but bought four phones on behalf of the defendant (=def). Def was present when pl signed the purchase papers with the company, taking the option of 36 months of use. Def stopped using the phones after three months and returned them to pl after an additional five months. As a result, pl has to pay the phone company for the phones. Two months later, pl worked out a payment plan with the company, which included charges for calls already made, the price of the phones, and interest for late payment, which came out to a total of 6,500 shekels. The company did not provide a detailed explanation of how they arrived at that sum. Pl demands that def pay the entire sum. Def is willing to pay 2,000 shekels for phone calls he made but not for the other expenses because he was unaware that his lack of use would cause those charges.

Ruling: Beit din established that it is pl who is obligated to pay the phone company, as the agreement was made and signed between them. However, def obtained the phones from pl with meshicha, by physically acquiring the objects in a manner that made him obligated to pay pl for their price. Both litigants agree that the deal was done as a favor by pl for def. Therefore, we view the deal between pl and def as an exact duplicate of the agreement between pl and the phone company. In this way pl neither gains nor loses from his agreement to, in effect (not by law), be the middleman between def and the phone company. It does not make a difference if def was aware of all of the conditions of the sale. If he had wanted to, he could have found out, certainly considering that he was present when the deal was being finalized.
Thus, def obligated himself to pay not only for the calls he made but also for the phones themselves should there be a need to pay for them. Since this payment is one of an accepted obligation, not a damage payment, it is not relevant whether or not def knew that his stopping to use the phones would cause a need to pay for the phones.
That being said, part of the 6,500 shekels charge was a result of lack of payment that resulted from pl’s delay in acting on the information that def was no longer using the phones. Pl is responsible for those charges.
Since beit din does not have access to the information that would enable it to determine the equitable breakup of those charges, beit din will estimate based on its authority to employ p’shara (compromise) so that the matter can be closed (see Shulchan Aruch, Choshen Mishpat 12:5). Beit din decided that def has to pay two thirds of the total charges.