I am going to suggest that you sit down with an attorney in person and discuss your questions.
You do not mention the age of your child. If the child is a newborn then usually the visits will be short and frequent - usually not over-night until the child is 3 years old - unless you agree to it voluntarily. If you are breast-feeding, then visits will be based around the baby's feeding schedule. As you can see, a lot will be based on the child's age and needs. If the child is over the age of 3 then usually there are over-night visits and the father can drive the child when he has visits.
It sounds like you have contacted the Texas A G office. Their services are free, but you are probably going to have to wait quite awhile for them to get to your case.
A private attorney can probably handle your case much quicker - of course, you are going to have to pay for their services. There are many excellent attorneys on this website & I highly recommend that you look on this website and try to locate an attorney to assist you. Many offer a free consultation via phone or in person. Many offer payment plans.
The child support is based on his net resources might is not just his paycheck - you can read about net resources on the Texas Family Code - available on-line. The percentage is 20% unless he is supporting other children and then it drops based on a formula - again in the TX Family Code.
Do you have to change the child's name? Again, that is negotiable. If the father wants it done, most judges will require it.
The Office of the Texas Attorney General has an excellent website with lots of information on it. The Houston Bar Association has an excellent website - look at the section "for the public". There are many websites with information regarding family law - but be sure to only read about Texas laws since family law is controlled by the state in which you live. This website has thousands of questions similar to the ones that you are asking -- happy reading!
Unless they have a reason not to, courts will generally allow the non-custodial parent to take children for the weekend. There are a number of good reasons that could grant restricted visitation but that's something I wouldn't be able to tell from what you've written.
If you have one child, generally a court will award 20% of his income to you. You do not have to give him his father's last name.
I would strongly recommend consulting a family law attorney.
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