There are two problems with collecting Blake Crouch books. I hope you can address them.
1) His first editions are in both the US and the UK. I lean more towards the US editions, but are they viewed by book collectors as true first editions? To collect both US and UK first editions gets very expensive and money can best be spent elsewhere.
2) Many of his first editions that you have for sale are paperbacks. Are there hard copies for these books? And, if so, should we be collecting those? Can you tell us which books were only published as paperbacks?
The true 1sts are the US editions, except those with simultaneous releases.
All of his self-published titles are only available as trade paperbacks, but are still collectible and required to complete any collection.
They include: Draculas, Eerie, Famous, Fully Loaded, Good Behavior, The Last Town, Pines, Run, Serial Killers Uncut, Serial, Stirred, and Wayward.
Hopes this helps.