As I am sure you'll be besiged with Realtors vying for your business very shortly, I wanted to answer you with facts and not a sales pitch.
Having a buyer's agent does not cost you anything and actually strengthens your negotiation ability when purchasing a home. You are also guaranteeing that your rights are being protected. Also, we can ensure that you are receiving current and accurate listings, rather than finding outdated ones on the Internet and wasting your time searching on your own.
Having a buyer's agent gives you an advocate. They are looking out for your best interest from start to finish. This person will fight for your rights and position throughout the home buying process. If you were to buy a For Sale By Owner, new home or through the listing agent of an open house, no one is looking out for you.
Any good buyer's agent is going to accommodate your schedule. Lockboxes only work during certain times and owners or tenants may put restrictions on when a home can be shown. Either way, a great agent is going to problem solve to get you into the homes that you want to see.
Realtors also have a strong network of allied resources that are invaluable. A lot of times, I call on my professional network for quick and thorough answers that a buyer or other agent without these relationships can't do.
Finally, in Virginia, we have 'procuring cause' which says that the agent who is responsible for you purchasing the home is the one who is owed a commission. You could get yourself in a bind where you sign a buyer agreement to hire an agent after you've seen the house with the listing agent. You could potentially owe both of them a commission. The listing agent because they were procuring cause and the buyer's agent because you signed an agreement.
Furthermore, the listing agent works for the seller. Their job, even while showing you a home, is to get the highest price and best terms for their client, the owner. A buyer's agent can walk you through the same house and point out issues that you need to consider: resale value, issues with the home, pricing, etc.
If you have any more questions, I'd be happy to answer them at 703-615-4862, BrendaRStone@aol.com or http://www.stonerealtyservices.com.
Good luck, Brenda