Did you know according to Article 11 of the National Association of Realtors Code of Ethics …
REALTORS® shall not undertake to provide specialized professional services concerning a type of property or service that is outside their field of competence unless they engage the assistance of one who is competent on such types of property or service, or unless the facts are fully disclosed to the client. Any persons engaged to provide such assistance shall be so identified to the client and their contribution to the assignment should be set forth.

Here are several articles dealing with choosing the right real estate agent.  These articles focus primarily on residential agents but the concept is the same for land agents.  Click the links below to read more.

5 Things to Expect When You Choose the Wrong Realtor

Top 10 Mistakes Sellers Make When Choosing a Realtor

10 Things to Expect From Your Real Estate Agent When Selling A Home