I have a double sided 10 x 30 basic billboard on Highway 99 in central valley, what is the going current rate a sign company is supposed to be paying? The contract is 20 years old and rates are low, it renews next year. The sign company has sent me a low offer, just need to know how to set my rent price. the sign is all metal heavy duty and the land is in a excellent location for view of both lanes of highway 99.