According to this spreadsheet compiled at Crit Role Stats, Caleb cast fortune's favor 36 times over the course of Campaign 2. Notably, fortune's favor has material component:
a white pearl worth at least 100 gp, which the spell consumes
Now, I know Caleb had at least one pearl, often used to cast identify (I quote its first use in this answer), but I do not recall Caleb ever buying more pearls or talking about the pearls being consumed for the purpose of casting fortune's favor. Am I remembering that correctly, or did Caleb routinely maintain a stock of pearls that were consumed by castings of fortune's favor, which I have just forgotten about?
The reason I ask is that I remember the spell being pretty good - a reroll on anything, attack, check, or save, at the cost of a 2nd level spell slot seems pretty decent, but having just reviewed the spell and noticed the 100 gp consumed component, it now seems like a pretty steep cost for a one-time reroll. I've been using the spell wrong, regarding my recollection of Caleb's use of it as an in vivo play test of the spell having no consumed costly components.