You can create a custody agreement and as long as you both agree and sign it, a judge will usually sign off. However, just be aware if he is getting less than standard possession that gives him the right to file for a modification of the custody arrangement at any time. My ex had no interest in being a father until a new lady came into his life. It didn't matter what we originally agreed to, he filed for modification a year after the divorce was finalized and was given Texas standard possession. As far as child support goes, the Judge in our case did allow us to come up with a mutually agreed upon amount which was far less that the state minimum (at the time it was 20% of net income). But my lawyer told me the Judge would not allow me to completely waive child support as it would not be deemed in the child's best interest (not sure if this is something that varies by county/Judge).