We have three boys - aged 6, 4 and 6 months - and having a 3rd was the best decision we've ever made. Yes, it is more work but not that much. Yes, it is more financially challenging but you will find a way. The dynamic between the three brothers is lovely and our family life has an added dimension. You will undoubtedly be happy with two but you will be just as happy - but in a different way - with three. I don't know the ages of your two but I doubt you will need more help if you do not work and they are currently at school. Go for it!