I'm so used to posting about titles in Robert Goldsborough's continuation of Rex Stout's Nero Wolfe/Archie Goodwin series, which are published by Open Road, so they go on sale a lot, that it feels odd to post a book in the actual original series. They almost never go on sale. But, here one is:
Before Midnight is about halfway through the series, and has dropped to $2.99 at Kindle and Kobo US.
Kindle US:
https://www.amazon.com/Before-Midnig...dp/B003L1ZWQW/
Kobo US:
https://www.kobo.com/us/en/ebook/before-midnight