Why don't you wait until #2 is born to figure it out? You can use a single stroller for your toddler and a baby carrier for your newborn at first. Having said that, I adore my double stroller. It's nice to have a place to keep them both contained. I also like the stroller because my newborn can sleep comfortably in it while I do other things with my toddler. It's also great for diaper changes! I have a Baby Jogger City Classic Double that I was able to get for $375!
Mommy to sweet and crazy 6 and 4 yo boys.