All of the Mercedes Drew Mysteries, by Barnaby Wilde, are enrolled in the sale. The first three volumes are small collections of short stories. Mercedes Drew is a motorcycle courier in London who doesn't especially like the police; Desmond Flowers is a detective on the police force. These are good, light mysteries with a bit of humor and just a hint of romance. The first book is apparently permanently free, the others are $0.99 each (50% off) during the sale. All three of these volumes are available as Mercedes Drew the Collection, which is currently $1.50 (50% off). I'd recommend going with the collection.
The fourth volume, Smile for the Camera, is a short novel. It's much more serious in tone than the rest of the serious. I didn't enjoy it as much -- I gave it 4 Stars instead of 5. It's currently $1.50 (50% off) during the sale.
https://www.smashwords.com/books/byseries/2927