@bitgidi With what you've said here, I would be cautious. At best, you're uncertain and it is unclear whether your husband is likewise uncertain or a definite 'Hell yeah!' It doesn't come across like a resounding endorsement, to be honest.
You might also want to consider the angle from your child's point of view. Is having a sibling a nett positive or negative? You've stated a financial negative, time with you is also halved (and probably more at the early stage), and environmentally, of course, fewer children is better than more. Whether they get along is, at best, a gamble. However, you might feel that the positives outweigh all these. But you know all of this anyway.
I guess what I'm saying, is bringing another life into the world is a huge decision. Take your time. If you need a year to make up your mind, then so be it.