The guys walk up to Tom Anderson's house and they see he's having a Yard Sale. As they make it to the main table, the boys are interested, as a hedge trimmer lies right in front of them. Though they wish to have it, Anderson explains that it costs money, which they do not have.
Soon, Tom gets a call from his friend Bill, the barkeep at the Veteran Legion's Hall, needing him to watch the bar for an hour due to his wife's colon acting up and needing to send her to the hospital. Though Anderson feels that he is busy, Bill brings up the subject about vets making a truce to one veteran to another by code of honor, and Anderson has Beavis and Butt-Head watch over the Yard Sale. At first they don't want to, but Mr. Anderson tells them that he'll give them 10% of the money they make and he'll throw in that hedge trimmer they eyed earlier, so they agree.
As Anderson walks off, Butt-head manages the front. As one of Anderson's neighbors and member of a church community group comes by for a nativity scene piece, Butt-head tells her it's 7 dollars, and when she asks about where Baby Jesus went to, Butt-head adds in that the baby is an extra $10- And to her disgust and shock, she asks him to tell Anderson that he can go to hell.
In the middle of this, Beavis gets the idea to literally sell whatever is in his house, mistaking it as "junk", and they jump on the idea immediately. In examples of what the boys come to sell, they pick extremely low, low prices, and to their lack of intelligence on cost of things, they get people to spend "all of their money" on the stuff in the house- feeling that they are properly "ripping off" their customers. In example, for Anderson's TV, Butt-head sells it $8, then Beavis sells fine china for $5. Butt-Head then estimates a table at 20, and four chairs for 8 apiece - For a fair deal, he decides to sell it all for $15. Beavis then sells a rare purple heart necklace (from when Anderson was in the war) for $5. They eventually come to sell everything in his house for a measly amount of money in their stupidly and humorous amusement.
When Mr. Anderson comes back, he is happy that the Yard Sale of his went over extremely well. Counting the money the boys made, he gives Beavis and Butt-Head the hedge trimmer and, to their dismay, $6. Beavis and Butt-Head are mad, only seeing that %10 means ten bucks, and that they get $6, while he gets all the money. Lecturing the boys that they need to get better at bargaining and pitching their wares to get a better price, they are irritated and angered at him.
As Mr. Anderson walks into his house however, he soon comes to regret letting the boys take over his Yard Sale- All of his stuff is now long gone, thanks to the boy's antics. Beavis and Butt-Head, angry at how he used them, leave mad and destroy one of his bushes.