For all the fact that this is one more "isekai MC with cheat powers builds a slave harem" story, this little arc actually felt like he kinda earned the ending, particularly when he went all Dawn Of The Final Day - time to do something crazy because I still don't have enough money.
And I love the fact that the slave trader led the MC by the nose during the initial talk about Roxanne, because the guy was thinking with his dick, but the second time around, the MC won't even drink the tea because he assumes it's poisoned.