When I first found out we were having twins, the first thought that went through my head other than a big fat F bomb, was double everything. Double the diapers, double the clothes, double the cribs, double the Bar Mitzvah's.. Ok I jumped ahead on that one, but it's something you gotta think about.
But really right now, it's not so bad as they are pretty good at sharing so double the toys really isn't too necessary. They have their own beds and kinda share clothes now that they are the same relative size (more on that to come).
The real kicker right now is double the birthday parties.. And in more ways than one.. We decided to put them in separate classrooms. We felt that they relied on each other too much and wouldn't branch out socially if the other was always there. So when they became toddlers at school, we put them in separate classes and it seemed to work fine. However they do still wait for each other when it's time to go to the playground, and I'm ok with that. It's also kinda cute. But since they are in different classrooms, they are making different friends. Good so far. However different friends means more birthday parties.
So the standard pretty much is there are two kids, you get two presents. So if it's the boys' birthday party, more often than not they will receive 1 gift each from the child guest. If it's a close friend of ours obviously both boys will be invited and there will be two presents purchased for that birthday child. However, when it's another child's birthday say in Max's class, both boys will get invited because the parent knows they are twins. We're trying to move away from that and have Max invited to his friends' parties and vice versa for Mitch. It's challenging as they've pretty done everything and gone most everywhere together for the better part of 4 years, but if we don't do it now, it'll be harder to do when they are older.
Now, if we can only figure out how they can drive themselves there, we'd be all set.