The wins!
1. The world: We have magic primarily based on folklore and superstition, but we also have consecrated gasoline and a binocular-like device made from the corneas of 13 hanged men. Neuland also has to contend with discrimination against the undead.
2. Characterisation: Ford and Neuland are really smart guys who know their craft. 

The losses
1. Pacing: For such a short book, the characters spend far too long dallying before entering the house. Literally, that only occurs 65% of the way in. There were far too many scenes that didn't add much to the story and could've been scrapped.
2. Characterisation: Tilda admits that she's never met men like our duo before [killers], but after going to the beach with them [yes, that happened] ONE TIME, she's ready to travel across the country with them.

Tilda also joins the gang at the end, and I sincerely hope that her wealth isn't used as an easy solution for all their difficulties in potential sequels.