How much is your monthly budget for your baby? (not including daycare)

We are trying to re-vamp our budget and are not sure how much to budget for our little guy. We are planning on EBF- but I am going back to work after 4 weeks- so that might change and we might have to suppliment a bit (i am trying to keep all options open with EBF!) And our day care is already budgeted- but how much should we budget for everything else?