Looking at adoption from Bulgaria!

Hi all! We are working on adopting from Bulgaria as well. We've identified a little girl from the waiting child list and are finishing up our home study and gathering documents for our dossier-so ready for the paperwork to be done! We're getting ready to pay a substantial amount to our adoption agency and both my husband and my parents are concerned that we might do all this work and get ready to travel or get over there and be told that the child is not available and there's nothing we can do, or she is available but not at all the same individual we were told about. I can't find any specific stories of this happening, but at the same time, I can't find anything to set my family's mind at ease either. Can anyone help?