French Polished Murder by Elise Hyatt

You don't stumble upon a series like the Daring Finds novels every day... Divorced mom, Candyce "Dyce" Dare is the owner of the furniture refinishing store Daring Finds. When she discovers decades-old letters inside an antique piano she's renovating, she becomes distracted by an investigation that puts her at odds with the letter-writer's very powerful local family.