Some strollers are like an advanced piece of origami to fold up, and some are extremely easy to fold and unfold. There is no reason to buy a stroller that is hard to fold and unfold… there’s no upside to that. Also, you’ll find yourself trying to deal with your stroller with one arm quite often. Keep that in mind as well.
If you’re going to be taking junior and junior junior outdoors a lot, then you’ll want a stroller with a canopy. Most strollers come with a canopy or something that provides shade for your kids. There are also plastic or waterproof canopies that you can purchase separately that will make your kids and the things you’re carrying waterproof. Too bad there’s not room for you in there.
Some strollers have simple lapbelt, while others provide better security than Pelican Bay. Most strollers now come with either a three point harness or a five point. A five point is more useful for infants because they’re always tipping over or sliding out of their chair. A toddler will do better with three point harness.