As to your question " if someone wants to buy my house 2 months later, and it happens to be someone who looked at it before why should I give any realtor any money" the answer is that they were the procuring cause that lead to you selling. The property was introduced to the buyer due to the efforts of the listing agent's marketing and the buyer's agent showing them your property.
Our listings and most agent's have a 180 day (6 months) broker protection period after the listing expires.
You can sell to anyone you like WHO WAS NOT INTRODUCED to the home by an agent during the period it was listed, but you freely admit this buyer saw the property during listing.
As you can see, what you suggest is not uncommon.
Just a few years ago, EVERYONE was an 'investor' type expecting agent to drive them about looking at home. As the agent is about to pull from the drive of the viewed home, the 'investor type; shouts...wait...leaps from the car and rushed to front door to hand owner their business card. The back printed read, 'Call me when your listing expires."
You don't need to be a brain surgeon to realize there are blockheaded investor type and brick minded sellers who celebrate the opportunity to do the wrong thing. What you are unawre of is there is nothing rare or new or novel on ingenious or smart regarding such actiivties. Such action only compels professionals to protect the effort and resouces they have invested in the process of helping an owner sell their home or the agent helping a buyer find a home. The community of professionals understand this also.
It IS because of the bricks and blocks out there that compel action that results in a 'get real people' response.
I understand. Folks often think they can eat the meal and not pay the bill. That is essence is what you are attempting to do.
I hope this answers your question.
Gloria Nilson & Co. Real Estate
If there is a breach situation between you and the agent's real estate company (most contracts are between you and the company not the agent), the consequences of going up against a real estate company especially a large company may get expensive. Please check with your local real estate attorney regarding the contract. Don't be foolish...be wise. Best of luck to you and thank you for the question.