And one more freebie:
Dire Straits, by Helen Harper (whose Slouch Witch series I loved), is the first in Harper's Bo Blackman series. It's free right now, and if you like this one, there is an omnibus of the whole series in KU, if you have that.
Kindle US:
https://www.amazon.com/dp/B00LMZF9HG
Kindle UK:
https://www.amazon.co.uk/dp/B00LMZF9HG