As the others have said, it doesn't sound like he has a real understanding of the reality of a new baby. You should keep negotiations open with DH, but don't push him too much until after the baby is born and he has a chance to see for himself. It may be that he has to reconsider drawing a wage for himself out of the business, or look into other avenues of financial support. maybe point out to him that there would be the cost of childcare (even if he is at home, he will be working!). But don't push him on it too hard too quick - because if he is anything like my DH and all the other males I know, he will get defensive about and even more stubborn and refuse to change his mind, or even consider other alternatives.

Also maybe you could look into a career change, a work at home job - or taking on a different time burden (ie, casual, part-time or after hours). find a job that suits your new lifestyle. I have a job that requires me to work as a casual, only a couploe of nights a week - the money isn't great because of the short hours, but without childcare costs etc, we seem to have about as much as if I worked fulltime. There are also options such as tupperware, Avon, etc.

Good luck with it all.