NOTE: every Incubator (full book project) includes the Nestbuilder program, so if you're exploring A-Z publication with Siretona or have already signed a contract, you don't need to sign up for Nestbuilder. 

However, if you haven't decided how to publish, or you know you're going to DIY (do it yourself), then Nestbuilder should be a perfect fit. You can always change your mind and upgrade later.