I ran across a “boxed set” of the first three Erast Fandorin Mysteries,
The Winter Queen, Turkish Gambit, Murder on the Leviathan at Kobo UK for only £2.99. If you don’t know these, they’re quirky historical mysteries/thrillers set in 19th century Russian; each is written in a different style. Very good, IMO, and you pick up a fair amount of history while you’re at it. I didn’t check the Amazon UK price but I’d guess it’s the same.
https://www.kobo.com/gb/en/ebook/the...orin-mysteries