What are the odds of a custody change if I take my X to court?

The mother of my child got custody over 5 years ago of our child. Our child is now 15 years old and has expressed many times over the past 2 years to me of wanting to live in my home. We are both remarried and have had more children with our spouses. My child expresses to me and my wife that her mother yells and swears at her often. I know the mother has a short temper not many patience and is a yeller and we do not communicate well together at all. In the past year there was a hitting incident where CPS was involved but my child had to go back to the mothers home due to the fact if needed he/she is old enough to defend his/herself if needed. There was a safety plan put in effect which was kinda pointless in my opinion, a safety plan would be getting her out of that home. The hitting hasnt happened since but the yelling and swearing continues almost daily. There is a medical report from the incident. She wasnt in any critical condition just some swelling. I want to have custody of my child and my child wants this as well. My home is a safe calm and loving home there is no yelling swearing or belittling in my home. I want to go to court to get custody and change the parenting plan but am afraid that with me having to change jobs in the near future and as much as attorneys cost these days I wont be able to afford a custody fight. My daughter wants to live in my home full time and I (my family as well) wants her to be in our home full time. Neither of us have thousands of $$ to spend on a custody fight but something has to be done. The mother knows I want custody but will not allow it and will put up a fight. I am pretty sure if our child told the mother flat out it would just make her angry and still wouldnt give me custody. The mother is VERY controlling. Has anyone gone through anything like this and what was the outcome. How much did it cost you or how did you go about it. Any attorneys or someone experienced with family law have any suggestions or recomendations for me and my family would be apriciated.What are the odds of a custody change if I take my X to court?
At the age of 15, most courts allow the child to choose who they want to live with. If the Mother is willing to fight this however, and has the funds to, your odds of winning without a lawyer are not very good I'm afraid!