A Real Estate Agent must be either a Buyers/Sellers Agent or a Transaction Broker, but cannot be both a Buyers Agent and a Sellers Agent, for 2 different parties, in the same transaction. The State of Colorado does not recognize, nor allow, a Dual Agency, although some other states do allow that.
If an agent is a Buyer's Agent for you, he/she must work for your best interests in the purchase of a property. Similarly, if an agent is a Seller's Agent for you, he/she must work in your best interest, as well. Now, if an agent is a Seller's Agent for the Seller, and you're the Buyer (but without an agent) then that agent owes you no duty, unless he/she changes his/her status and becomes a Transaction Broker, in which case that agent works for the Transaction,, not either party.
Feel free to email me if you have further questions at Sean@HawaiianShirtGuy.com. Best of luck!