35
Ruling: Added expense of materials – Since this was not in def’s contractual obligation but he was asked to do so as a shaliach doing a service on pl’s behalf, pl is required to pay whatever reasonable price def paid for it (def provided valid receipts). Only if def had overpaid would pl have a claim (see Shulchan Aruch, Choshen Mishpat 182:3).
Charges for changes – The misunderstanding occurred largely because pl interacted with def’s workers rather than with him, and they suggested improvement without discussing price. On the one hand, it was wrong of def, who knew about the changes, to not inform pl of their cost, considering pl’s running a tight budget on the project. Although the contract mentions price modifications for changes, they should be clear. On the other hand, charges for changes to building projects are normal, and it is not always feasible to stop the work each time to negotiate its price. The majority of the dayanim put the onus on def, who is the professional in this matter. On the assumption that pl would not have wanted the improvements at the price def demands, def is considered like one who did work for another without permission. Although the property owner must pay for any benefit from the work, our case is considered like that of one who tells the worker to take back his additions, who is exempt from paying (Shulchan Aruch, CM 375:6). According to one dayan, def should not benefit without paying anything for it, and the idea of taking back additions does not apply here because it is unfeasible here to undo what was done, and therefore 30% of this claim should be accepted.

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