I have 2 children. DD is 5 and DS is almost 3. I am desperate for another baby, in fact I'd really like another 2 children and have a family of four but practically one more is probably my limit.
However we live in a 2 bed house which because of debt and taking out a mortgage over more than the 25 year term and a 100% mortgage we're in negative equity on and I can't see how we're ever going to be able to afford to move out. Neither of us earn much although we earn enough to keep us from being eligible for benefits. Part of this is DH, he could go for promotions etc but is happy where he is and doesn't want to add to his responsibility. I work part time.
Since we already have a DD and a DS in one bedroom I can't see how it would make much difference to add another. If I had two DDs it might be different, they could share indefinitely but as it is they have to share anyway. And I do worry about that too. At what age will DD need her own space?