Negotiating a mineral rights lease

I had a mineral rights lease with J Cleo Thompson that expired at the end of October. They have told by brother that they want to do another lease, but they haven’t offered any terms yet. When we signed the original lease we just took the terms they offered. I only own 8 acres in Gaines County located at League 297 Labor 22. I have heard that there are individuals or companies that will negotiate for you, but I am not sure with such a small number of acres if it would be worth paying somebody. Does anybody have any information on how much they charge for negotiating?