How to build my case?

Have you ever heard of lawyers working Pro Bono? Pro Bono work is work that lawyers do without pay and depending on what state you live in they may be required to volunteer for a certain number of Pro Bono hours. Use the internet to search your local area for a Volunteer Lawyer Program or something of the like. That would be my first recommendation. Keep in mind that these Pro Bono lawyers have a lot on their plate so they may not be able to take your case. If you are unable to get a volunteer lawyer then of course you can represent yourself. From what you have given me here you have a pretty good case. You could try to sue for full custody of your daughter but I would stress that you get both her TSS and her behavioral specialist to testify. Without the testimony of both of them it will be very difficult, but utilizing them will win you the case more likely than not. My first recommendation is safer, but do not lose hope if you can't find a volunteer lawyer because you still have the option to make your own case with the expert testimony.