Mr. Sam Braun stood at the back door of his house with another man, surveying the back yard. The man, who had a tape measure in his hands, took measurements along the length and width of the yard.  Sam’s neighbor, Hillel Farber, sat in the adjacent yard.

“What’s going on, Sam?” Hillel called out. “Who is that?”

“We’re doing some renovations,” answered Sam. “This is the contractor, Tom Green.”

“What are you building?” asked Hillel.

“I’m adding a deck in the back of the house and a wooden structure for the kids to play in,” Sam answered. “I’m also considering building a wooden fence to separate our two properties. What do you think of that?”

“That’s a good idea,” said Hillel. “It would also give us more privacy.”

“Are you willing to split the cost of the fence?” Sam asked.

“Could be,” replied Hillel. “How much will it cost?”

Sam turned to Tom. “What do you expect the fence to cost?”

“In the range of $2,000 to $3,000,” said Tom. “It depends on the exact measurements and the type of wood we’ll use.”

“Fair enough,” said Hillel. “I’m willing to chip in and pay half.”

Sam decided, in the end, to run the wooden fence around most of his property.

When Tom finished the work a month later, Sam said to him: “You remember that my neighbor said he’d split the cost of the fence between the properties? How much was that part of the job?”

“It’s worth $3,000,” Tom answered. “Let him pay $1,500.”

Sam told Hillel that the fence cost him $3,000.

“Can I see the invoice?” asked Hillel.

“The invoice is for the entire job,” said Sam. “The part of the fence that we share is not listed separately, but $3,000 is what Tom told me it’s worth.”

“If you don’t mind,” said Hillel, “I’d like to double-check with another contractor about that valuation.”

“I don’t mind your checking,” replied Sam, “but I think we should follow Tom’s appraisal anyway, since he did the work.”

Hillel spoke with another contractor who said, “That kind of fence generally runs about $40 per foot.”

Hillel calculated that the shared part of the fence, which ran 60 feet, came to a total of $2,400. “Based on what the other contractor told me,” he said, “the fence is worth only $2,400.”

“Who’s to say that his appraisal is more accurate than Tom’s?” Sam replied. “Anyway, as I said before, Tom did the work.”

“But he didn’t give a clear price beforehand for the shared part of the fence,” argued Hillel. “At this point, his appraisal is no different from anyone else’s. Why should I pay more than it may be worth?”

Sam scratched his head. “Maybe that’s what the other contractor charges, but Tom charges more,” he responded. “I suggest we take this up with Rabbi Dayan.”

“Great idea!” exclaimed Hillel. “I’ve been waiting for a chance to ask him a business halacha question!”

Sam and Hillel met with Rabbi Dayan, who said, “In general, when a person agrees to have a job done and no price is stipulated, if there is a fixed going rate, he must pay that amount (C.M. 331:2).”

“What if there is a price range?” asked Hillel.

“Then he only has to pay the lower end of the range,” answered Rabbi Dayan, “in accordance with the principle ‘hamotzi mei’chavero alav hare’aya’ - the burden of proof is on the plaintiff. This is true even if most people charge a higher price (Ketzos 331:3).”

“But I stipulated a price with the contractor,” objected Sam. “Hillel agreed to reimburse half the price that Tom charged for the fence.”

“That is correct,” said Rabbi Dayan. “Had Tom stated a specific price for the shared fence, Hillel would have to pay whatever it was, even if there might be a cheaper contractor. However, no explicit price for the shared fence was given.”

“Then how do we evaluate it?” asked Sam.

“Since Mr. Farber agreed to the work of this contractor,” said Rabbi Dayan, “Mr. Green should give a clear calculation of his appraisal — according to his billing standard, or as a proportion of the entire fence — and Mr. Farber must pay that (Pischei Choshen, Sechirus 8:[11].”

I am a scribe, and someone gave me a pair of tefillin to examine. I took the parshiyos out of the compartments of the shel rosh and noticed that the threads of hair wrapped around them (O.C. 32:44) were extremely tight. Since the parchment was old, the hairs had already notched the parchment somewhat; as I removed the threads, I extended the notch further into the parchment. After the parshiyos were opened and examined, it was clear that the notch was deep enough to invalidate the parshiyos.

Q: Am I obligated to pay for the damaged parshiyos?

A: If you were certain that the damage that you did to the parshiyos invalidated them, you would be liable. This would be no different from a professional who damaged an object while repairing it. Shulchan Aruch rules that a paid professional is similar to a paid shochet who is liable if he slaughtered an animal, and in doing so, rendered it non-kosher (C.M. 306:4). In such a case, it would be necessary to determine the exact value of the used parshiyos that are brittle and could be easily ripped.

As a rule, a repairman is a shomer, or custodian (C.M. 306:1). If it is uncertain whether he is legally responsible for the damaged object, he is obligated to pay. For example, if there is doubt whether he behaved in a negligent manner, he must either take an oath that he was not careless or reimburse the owner. If the custodian is himself uncertain whether he was negligent and for that reason cannot take the oath, he must pay (mitoch she’eino yachol lishava meshalem).

In your case, however, there is an additional factor. It is possible that the parshiyos were damaged before you ever received them and may have already been invalid (see Shaarei Yosher 2:17). If that were the case, you never became a custodian of valid parshiyos and the halachic category of “eini yode’a im nis’chayavti” applies. This means that a defendant is not legally responsible if there is uncertainty whether he ever became obligated to pay the claimant (see C.M. 296:4). Furthermore, if the claimant is also uncertain whether the defendant was ever obligated to pay, there is not even an obligation on the defendant to satisfy the standard of latzeis yedei shamayim, beyond the letter of the law (see Shach 75:67).

Since it is uncertain whether you received damaged parshiyos, you may have never become a custodian of undamaged parshiyos. Neither can your customer claim that the parshiyos that he gave you were kosher. You are therefore exempt from any responsibilities as a custodian, even beyond the letter of the law.

Q: What are the responsibilities of a guardian for chametz on Pesach?

A: The owner of the chametz violates the prohibition of possessing chametz, even if it is entrusted to another. In addition, the guardian also violates the prohibition of possessing chametz if he accepted responsibility for it, even if it belongs to a gentile (O.C. 440:1; Mishnah Berurah 443:14).

If neither the owner nor the guardian sold the chametz, it becomes prohibited and has to be destroyed. Therefore, if the owner hasn’t sold the chametz, the guardian should sell it in time, both to avoid the prohibition and to prevent the loss (C.M. 292:17-18; O.C. 443:2).

There is a dispute whether the guardian carries legal liability if he neglected to sell the chametz. Some say that the guardian is considered negligent, so even a shomer chinam is liable; some say that only a shomer sachar is liable, since he has a greater responsibility to protect the item. Many maintain that the guardian is not liable, because he accepted responsibility only to guard the chametz, not to sell it. [It is questionable whether this logic would apply nowadays, when it is customary to sell the chametz before Pesach and buy it back afterwards.]

(See Mishnah Berurah 443:12; Pischei Choshen, Pikadon 2:[103].)