What went into planning a trilogy?

Thanks so much for having me on the blog today, Diane!
When the town of Bloo Moose popped into my head several years ago, I knew I wanted to set more than one story in the town.
Planning a series requires more planning than writing a single book. Each book in this series is a standalone. The setting remains Bloo Moose, but every story has a new set of main characters as the focus. This makes it different than a series with one or more main characters throughout the series. Each type of series requ...