Aaron Elkins is probably best known for his wildly enjoyable IMO Gideon Oliver (forensic anthropology) series, but he also writes a couple of art-themed series that I really like: the Chris Norgren series and the Alix London series. And Loot mixes the art background with the last throes of WW II to make an enjoyable stand-alone mystery with some thrillerish bits. It has dropped to $1.99 at Kindle US right now.
Buy at Kindle US
Turncoat is another of Elkins’ non-series titles, and it’s $1.99 right now at Kindle US: https://www.amazon.com/dp/B00J84KO14