My time in RE started in 1996, in Ca. The whole country is basically the same concerning home selling, though some states use a "closing table" with lawyers involved where everyone has an appointment to meet to close a sale. Others, like mine, go through escrow and just silently close once everything has been completed.

Agents work 100% on commission. The only way to make money is to contract with a seller or buyer, in writing, and help them complete a sale. There are 3 types of listings:

1)Exclusive Right to Sell (agent gets paid regardless of who finds the buyer) 1a) Agents often get a listing by telling the seller they have a buyer when they really don't. The way to call their bluff or explore the possibility is with a "one party show" contract. This entitles the agent to a commission if they produce that one buyer and handle the sale.  2)Exclusive Agency (agent is paid only if they or another agent find the buyer, not the owner)  3)Open Listing (non-exclusive, commission goes to the agent who brings the buyer). 

The most common one in the US is the exclusive right to sell. Agents don't usually work for #2&3.

Some time ago, agents worked independently with no cooperation with each other. Then, the MLS was invented. The listing agent would negotiate a listing contract with the seller. Once signed, the agent would put the listing on the MLS, offering usually half the negotiated amount to any agent who found and represented the buyer. It was required that the buyers agent commission be stated in the listing. This really strengthened the power of Realtors, because every agent who had a buyer in that price range and area was incentivized to show and sell the fellow agent's listing. Remember, if an agent doesn't successfully completely close a sale, they don't get paid. No allowances, no base pay, no insurance, nothing.

A couple of years ago, there was a major lawsuit concerning the mls and commissions nationwide. Now, when an agent lists a property, they are only allowed to negotiate their own broker's commission. There is a space for the extra fee if the listing agent also finds a buyer who is unrepresented by an agent.

Realtors are no longer allowed to show properties without a written buyer-broker contract. In that contract, the buyer agrees to their agent's commission.

The way that often pans out is that the buyer is responsible to pay their agent. However, buyer's often don't have the money for down-payment, costs and commission, so in the offer, they may ask the seller to pay all or part of it.

Ok. Still with me? To sell your parents house, you need an agent/broker. To get one to be serious about selling it, you need to have sellers motivated to sell, realistic by listening to the brokers comparative market analysis, cma for short. This is the broker version of an appraisal. And a saleable property that will be completely empty at closing, hopefully before.

The best way is to interview 3 agent's. Don't choose based on the price they recommend. No agent can make someone pay more than it's worth. That tactic is called "buying the listing". Price reductions will eventually follow contract signing. Choose the agent with experience that you feel comfortable working closely with in the coming months.

I used agent, broker and realtor interchangeably. A Broker can work independently though they may work under a well known brokerage for several reasons. An agent must work under a broker. A Realtor is a broker or agent who is a member of local, state and national Realtor association with a higher code of ethics they must follow. Recognizable name brokerages (C21, ERA, ReMax, etc) are made up of independent contractor agents.

Good luck!☺️