Thank you for the question. The answer is no. For residential and some commercial purchases of real property, you do not need to pay your real estate agent separately in order to purchase a house.
The main reason for this is that it is customary that the seller pays the commission on both the listing side and the selling side. It is important to understand that the seller pays this directly from the proceeds of sale. The agreed upon commission is negotiable and the seller has many opportunities to verify the commission of the sale within the body of the listing agreement. The buyer benefits from this agreement because the seller is paying the commission.
Some say that the commission raises the price in home sales and that the buyer is effectively paying the commission because the buyer is paying the full purchase price. While this may be true, the seller cannot afford to artificially raise the price of the home to cover the cost of the commission. It is important to remember that the home will sell for what the market is willing to pay. If the seller raises the price to cover extra costs, ceteris paribus the home will not sell.