I work in Fulton regularly. 

If your sister is physically going to the county to make regular copies by herself, the fee is $.50/copy. 

(She can also take pictures of the book if she has a scanner app on the phone). 

If the county clerk makes the copy, I believe it is $1/page. 

If you are needing a Certified copy, the fee is $2.50 for the first page and $.50 for each additional page. 

The $25 fee is usually if you are in need of someone else (like myself) to go get the copies for you.

I hope this helps.