The author is an old man, like Fred. He doesn't tweet or twitter or even quack. He spent most of his adult life as an electronic engineer for the FAA and for the Navy. The last 12 years of his career was spent working in his wife's Christian bookstore. He considers those the best years of his life.
Fred and Mabel have moved to an assisted living facility. Because of the company's loss of a large sum of money, the facility may be forced to close, and all the folks seek new places to live. Fred is eager to find the lost money, but has no accounting knowledge, so Mabel must step in. Almost all of the folks from the previous books help and in the end there are some romances and a twist in the adventure.