Why did the sailing trip of Jerome and Hector cost them a pretty number of week's pocket-money?

The two men were inexperienced and made more than a few mistakes. In the end, they got stuck in the mud, had to be twoed out of the mud, and had to tip the man who towed the boat. 

What between tipping the man who had brought us home, and paying for the broken sculls, and for having been out four hours and a half, it cost us a pretty considerable number of weeks’ pocket-money, that sail. But we learned experience, and they say that is always cheap at any price.