This is exactly what he meant by not listening to everything Karsa had to say. He just didn't think that would be the first thing she brought up, and the answer is obvious in his face before he replies.

"Travel is expensive." Can he help that his ability makes it extraordinarily easy to get inside a vault? He couldn't anticipate everything that came after, but it's really not a big deal. Almost a humorous anecdote at this point. "We're well funded for the immediate future. That's all you need to worry about."

Mostly because Five kept a good portion of the loot hidden from the rest of them so it hasn't been entirely depleted. He was exhausted for days after that, he's not trying to go through it again. -- And he'll be changing the subject now.

"We survived the worst of it. I'm hoping there aren't any other undead warlords where we're headed, but we'll find out soon enough."