The Kumquat Legacy

The Kumquat Legacy is an free e-book by Randal Koster which I downloaded from Smashwords.  This e-book was meant for young readers (age 10 and up).  I am much older than age ten but as someone who substitutes sometimes and a collector of children's series books, I do like reading books meant for different ages.

Dave, a 13 year old, is chosen by a rich man to possibly get the Kumquat Legacy.  The legacy will be his or the man's nephew, Cyril, depending on who can solve all the puzzles and get the combination to a safe first.  The reader is given an opportunity to try to solve the puzzles before reading the answers.
I would certainly recommend this e-book to anyone who enjoys mysteries.