How much to pay for a trip in hired transport that was stopped halfway

Shalom.

A family ordered a van from Modiin Illit to Kiryat Ata on Erev Shabbat. The driver lives in Rechasim, and they hired him so that he would be able to get back home for Shabbat. In practice, there were several accidents on the way, and they arrived near Rechasim close to sunset, such that if the driver would take them on to Kiryat Ata he would not manage to return home. Therefore he stopped in Rechasim, and they ordered a taxi to Kiryat Ata. The question was asked: how much, and whether, they need to deduct from the driver’s payment — the entire cost of the taxi, or only the difference between a trip to Rechasim and a trip to Kiryat Ata? Or perhaps they should not reduce his fee at all?

Shalom u’vracha.

From the driver’s payment you deduct the amount that the taxi cost.

The Gemara in Bava Metzia 79a says: “One who rents a donkey and it dies halfway along the way, he gives him the wage for half the way.” Tosafot and the Tur explain that this payment for half the way applies only if the owner has something to do at that halfway point; but if he has nothing to do there, the renter is exempt from paying altogether. The Rema brings their words in Choshen Mishpat 310:2. In our case, although the ones (unforeseen accident) concerns the worker and not the vehicle itself, nevertheless, since he did not complete his work and brought them only halfway, they are obligated to pay him only according to the benefit they received from that half of the way, and no more. And since the benefit from half of the journey is measured by how much it costs them to reach their destination from the halfway point, they therefore deduct from his fee the amount it cost them to complete the way; without this, they would have no benefit at all from half the journey.