I'm going to start querying agents soon on my current manuscript, book 1 of a projected trilogy. Based on what I've learned from this forum and agents' blogs, I should work on a completely different project at the same time because even if you get signed by an agent, he/she may not be able to sell this book and will ask to see something new from you.

I'm ready to start a new series, but here is my question: Should I get the outline done for book 2 in the trilogy in case an agent requests it? Or it can wait until a publisher shows interest? I'd rather postpone that and pour all my energy into my new series if it isn't necessary.