Standalone or Series?

As readers, do youprefer standalone or series? As a writer, I have written both. My first publicationwas the six book Paul Jacobson Geezer-lit Mystery Series. I also have severalbooks with sequels: The Back Wing and The Front Wing; Court Trouble andParadise Court. I also have the Omnipodge Trilogy of Old Detectives Home, LastGasp Motel, and A Mystery Yarn. My other nine published books are standalones.The reason for standalones are that I get an idea and want to pursue it eventhough it might not lead to a series. Some examples: Unstuff Your Stuff is a mysterythat came about because I got interested in what professional organizers do.Murder in the Museo Kircheriano is a historical mystery based on the fascinatingcharacter Athanasius Kircher who was know as the last man to know everything.The Tesla Legacy is a thriller based upon inventions of the brilliant inventorNikola Tesla. Mystery of the Dinner Playhouse came about because of familymembers who have been in the theater world. Murder on the Switzerland Trail isa historical mystery set in the mountains of Colorado where I hiked on all thepublicly available sections of what had once been a narrow-gauge railroad bed.The Best Chicken Thief is a biography of a World War II veteran I met who wasin the infantry in Europe, captured by the Germans and liberated by theRussians. The VV Agency is a paranormal private investigator novel and happenedbecause my then agent suggested that I should explore a paranormal mystery. Theidea for Death of a Scam Artist came about when I became intrigued with elder abuseand people who preyed on seniors. My upcoming middle grade mystery, TheAdventures of Sure Luck Holmes, which will be released in November can become aseries.