My recent MS for YA is written as a series. There's no question about it, and the second an agent or editor reads the last page they will know there's a sequel. Is that a definite bad idea? I know there's plenty of threads about not pitching a series or even mentioning it in a query. Even if I didn't say it at first, the full manuscript is designed for a sequel (and possibly two books after that). Does that decrease the chances of it ever getting published?