A Drop of the Hard Stuff is the seventeenth in the Matthew Scudder series by Lawrence Block. It has dropped to $1.99 at Kindle and Kobo US.
Kindle US:
https://www.amazon.com/dp/B0047Y178O
Kindle US/Smile:
https://www.amazon.com/dp/B0047Y178O
Kobo US:
https://www.kobo.com/us/en/ebook/a-d...the-hard-stuff