To answer the original question it depends. Some Judges don't double check the Child support calculations some do. All should. If y'all have agreed to a deviation from the guidelines there should be a good explanation for it. (Again if the Judge is paying attention). If you are seeing the child significantly more than standard visitation that is typically a good enough reason for a small deviation.
Child support is 5th grade math. The variables are the parties income, other child support paid, health insurance and daycare. Period. It don't make a rip what your other bills are. Frankly I have little patience for men crying about paying child support. And yes you should give the other lawyer your tax return if you are operating in good faith.