What is involved with obtaining guardianship and what is the average cost? Can someone get free help for this?

I live in Fort Worth, Texas, and I'm trying to help my brother and sister-in-law in Williamsburg, Virginia. My brother has dementia and is no longer able to make decisions. My SIL is bed-bound. She is working with an attorney who is telling her that she needs to name a guardian, that it has to go through the court, and it will cost $7,500. They can't afford this. They have a live-in caregiver whom they want to have guardianship of both of them. Does $7,500 seem reasonable, even if they could afford it? How can they obtain free or at least low-cost assistance? They also need help drafting basic wills.