Final answer:
Owner A and Buyer B need to reach an agreement to establish an easement for access to the county road. Easements grant the right of use, not ownership, and they require clear terms to be set based on property rights defined by law.
Step-by-step explanation:
In the scenario where Owner A sells a piece of his property to Buyer B and requires access to the county road via Buyer B's property, an easement is necessary. Easements are rights to use the property of others for specific purposes. The establishment of an easement does not typically require Owner A to pay Buyer B a monthly fee, nor does it obligate Owner A to build a road for Buyer B. Instead, it requires an agreement between the two parties on the easement, giving legal access to Owner A through Buyer B's property. Therefore, Option 3: Owner A and Buyer B must agree to the easement is the correct course of action to accomplish this.
It is important to clarify that having an easement agreement in place does not automatically grant ownership rights of the land to Owner A; it simply grants the right of passage. As the Coase Theorem suggests, clear definition of property rights is crucial in resolving issues and avoiding conflicts between parties. Once property rights are established, the parties can negotiate the terms of the easement, potentially including maintenance responsibilities or usage limitations.