When purchasing a house, it's best to use a buyer's agent who looks out for your interests, instead of working with an independent agent or listing agent, who looks out for the seller's interests. However, there are some things to watch out for before signing a buyer's agency agreement.
Make sure that the agent who is supposed to represent you, or a colleague from the same agency, isn't working for the seller as well. Dual agency can lead to conflicts of interest and ethical dilemmas. If you sign on to work with a particular agent but forget to specify that you specifically want a buyer's agency agreement, by default the agent will represent both the buyer and the seller.
Be aware that agents get commission on the homes in their agency's listings so they are partial to those homes, pitching those sales harder. Furthermore, it's understood that if you buy a home through an agent, that particular agent gets commission on the purchase. However, some agency agreements contain clauses that state that the agent is entitled to commission on any home you purchase, whether through the agency or on your own. If you feel that it's possible for you to purchase a home on your own, remove that clause from the contract before signing the buyer's agency's agreement.
One last item to include before signing on with a buyer's agent is a release clause. If you don't want to continue working with a particular agent, for whatever reason, there should be a safe outlet set up in advance. In this case, any houses shown to you under the old agent would potentially entitle him to commission, whereas after parting ways, any new houses you see on your own or through a different agency would entitle the new agent to the commission.