What information is available to a royalty interest buying company evaluating a  tract of land to arrive at an offer price for royalty interest for a potential customer before drilling has begun in a section?  Are they looking at production rates from current nearby wells?  Is there some math formula a landowner might use in hopes of determing if a current offer is fair or not ?   How do royalty buying companies arrive at an "educated" dollar offer amount  that landowner  gets in the mail and  does not know about while no wells are being drilled in the section but are being drilled in nearby sections?   How can a landowner insure that an offering royalty interest company has made a current fair price for future, unknown production revenue (s) before a drilling operator drills in a section and just accept a  price offer blindly, which may winding up being foolish in the future???   This is not a question if one or one does not need the immediate cash.  Thanks in advance for your information.