(Mishnah): One who rented a donkey to bring wheat and he used it to bring barley (of the same weight); or he rented it to bring grains and he brought straw (of the same weight), the renter is liable.

Question: How much must he add onto the load to be liable?

Answer (Sumchus in the name of R. Meir): A seah for a camel and three kav for a donkey.

Beraisa: How much must he add onto the load to be liable? Sumchus in the name of R. Meir said - A seah for a camel and three kav for a donkey; a kav for a person carrying on his shoulders; 3 seah for a calf and for a boat, it depends on the boat.

If a caravan of travelers was attacked by bandits (who are coming for money rather than to kill, if they agreed to settle on a certain sum rather than take hostages), we calculate according to the worth of the people rather than the number of people.

If they had sent a guide ahead of them, we calculate according to the number of people.

We do not change from the custom for a caravan - whether it is to pay per person or according to their worth.

If a boat was in a storm and they lightened its load (by throwing some items off from the boat), we calculate according to the load, according to their wealth and according to the number of people.

But if one rented a wagon or a boat, we calculate according to the load or the people but not according to their wealth.

If a caravan of travelers was attacked by bandits and one of them overcame the bandits and saved all of their money, each of them is returned his money. But if he had told them that he is saving it for himself and they were silent, he receives all of the money (as the owners had given up hope of recovering it).

If donkey drivers were attacked by bandits and one of them overcame the bandits, each of them is returned his money. But if he had made a stipulation with them in Beis Din, he receives all of the money.

If partners were forgiven from paying by the tax collectors (after one of the partners approached the collectors to request it), each is returned his money. But if (they were not first approached by one of the partners and) the tax collectors said that they had forgiven it for ploni (a specific partner), only ploni gains.

It is difficult for the king's duty collectors and the tax collectors to repent (as they often collect too much tax for people) - they must return the money to any person that they recognize that they overcharged. As for returning money to those that they do not recognize, they should give the money towards communal needs.