With both of my ex-wives we reached an agreement for me to pay child care up front for the whole of their childhood. After that money hit their bank account they went after me through the courts and won. The courts said that private agreements would not be taken into account. So in my case, yes I did get screwed twice over and lost everything and ended up virtually living on the streets. I have had contact with other men in a similar situation. How widespread it is I do not know, but it is not uncommon. To make matters worse I not only paid child support twice over, i got refused access to my kids and have not had contact with them for many years.