The first and foremost importance of using a buyer's agent is the agent is working for you! Second, they will help you with your search of homes within your criteria and negotiate on your behalf to get the best possible price for the home. Third, help with arranging home inspections, mortgage pre-approvals, and get you to the closing table with the least amount of stress as possible.
I remember when I bought my first home. I thought that we were suppose to use the agent that was listed on the sign in the yard. Boy!, were we wrong. We called the agent, they show up, we go in the house to take a look. We liked the home so we put a contract on it. The agent facilitated the paper work to submit our offer to the seller. Had all the necessary inspections done. Every thing was going good. Closing went as scheduled so we thought WOW, this was easy. The horror started the day we started to move in. Showed up at the home, realized that there was this smell in the carpet, you guessed it, they had cats. Ripped all the carpet from the home, that exposed a area of rotten flooring. Had to repair the floor before we could replace the carpet. And I could just go on and on. It took us 3 weeks before we could actually move into our 'dream home'.
I don't want my clients to ever have to encounter this sort of nightmare in the purchase of a home.