While the mystery part of this book was quite interesting (although I figured out the point much sooner than the MC), I did not enjoy the rest. Maybe it was because the book started when the MCs already knew each other, but I couldn't feel the attraction between them - they seemed to have so different world views and, apart from the lust, I didn't get why Finn liked Max and vice versa (Max did explain it a bit at some point, but why would he value the free spirit in Finn when he didn't want someone like that (who sounds like a great teacher) to tutor his relative?). I can't see them having a future together.
Something else that annoyed me was how the "bad guy" was described - in the finale, when the culprit was exposed, the author constantly drew attention to them being overweight, with every other sentence having "meaty", "beefy" or "puffy" in it. This wasn't necessary at all, so it just came over as a cheap way to show them as unattractive. Fat-shaming is not cool, and if I hadn't already bought one more book in this series, I wouldn't.