Great question! Many buyers are not sure where to start if they find a home that they like and would like to place an offer. Most may contact the listing agent (call the phone number on the sign) and have them handle it. Not always a buyer's best move. That agent represents the seller.
A buyer's best option is to locate a buyer's agent to represent them solely in the purchase. The buyer's agent can help structure an offer to the buyer's best needs as well as compare the home's offered purchase price to the other comparable homes in the area to ensure the buyer is not paying too much for the home.
It's a good idea that a buyer interviews a few buyer's agents to see who will best meet their needs for a comfortable working relationship.