All In Good Time — Jeff Newman

John Upham is happily living his bachelor life as a lawyer in a small New England city when a friend pulls him into a treasure hunt. Barley Overshot is a wealthy playboy and one of John's clients. He is obsessed with finding the long lost Mayflower Compact, the first American governing document. It is a national treasure that has been missing for a long time and he has a theory to help them find it. But finding a document that has been missing for two and a half centuries is never easy. If they are going to succeed they will need to confront ghosts from the past and ghosts within their own lives.
The Mayflower Compact was signed on board the Mayflower by the Plymouth families. It was an agreement by all about how they would live together as a settlement. It was copied several times before being lost. Barley has done his research and believes that the Compact was smuggled out of Boston during the Revolutionary War by a secret agent and hidden in a particular tavern in New Hampshire. If the story holds, they still don't know how it was hidden, or where. The old building that they focus on is haunted by more than old remedies. John and Barley have to find out if an ancient force is trying to guide them and why. Along the way, John finds more than he expected to find at the beginning.