From Nookipedia, the Animal Crossing wiki
Lyle (ホンマさん, Honma-san) is an insurance salesman that appears in Animal Crossing: Wild World, Animal Crossing: City Folk, and Animal Crossing: New Leaf. He is a blue, spectacled weasel with large whiskers and a hunched appearance. He works as an insurance man in Wild World, selling insurance and giving refunds on forged paintings. In City Folk, he has a new job, working for the Happy Room Academy in their headquarters in the city. In New Leaf, Lyle continues working for the expanded Happy Room Academy, where he is stationed in Nook's Homes. His species is based off another name for a scammer, a "weasel."
Lyle makes his first appearance in Animal Crossing: Wild World working as an insurance salesman. He appears every Saturday between 6 am and 6 pm outside the player's house to take a survey. He will follow the player for a time if they do not talk to him immediately, a sign of his persistent nature. Upon talking to him, he will ask a number of unanswerable questions, heckling the player into signing a health insurance policy. The only way to avoid this is either by declining to take the quiz or by not having sufficient funds (which will "bust his chops").
By paying 3,000 Bells, the player will receive 100 Bells every time he or she is injured - this includes tripping or getting stung by bees. However, players can receive the 100 Bells bonus only once per day. A further payment of 6,000 Bells on the following Saturday will result in the players' receiving compensation of 100 Bells if they buy a counterfeit painting, but only if the painting is presented to Lyle himself.
Some jock villagers also say the same thing - how this "guy" came and asked them if they wanted their muscles insured. At first they said no, because "whoever's heard of insuring your muscles?" and that another villager told them it was a scam.
Lyle is also believed to be working with Redd, scamming people out of money. In his questionnaire, Lyle asks for what weekday Redd should appear in the town, after which Redd will appear on that day, but will also deny any connection with him.
Lyle appears to have a more respectable job in Animal Crossing: City Folk, working in the Happy Room Academy Headquarters in the city. He will mention how much he hates his new job, and frequently talks of his old, "high-flying" lifestyle. He seems to be calmer, possibly to fit in with his new "happy" job and only makes a reference to "bustin' [his] chops" once, if the player refuses to join the HRA. When talked to, his persistent nature leads him to continue talking with the player until they agree to join the Happy Room Academy. If the player's house becomes the model room, he states (if they decide to discuss the model room with him, not the evaluation) that he is trying to love his new job. An ad for the HRA, with his picture on it, can be seen in the bus, behind Kapp'n's seat.
He makes no reference to his past lifestyle in Animal Crossing: Wild World other than his frequent complaints and mentions of his old office when the player first talks to him. He does not talk about Redd or Crazy Redd's, which is located nearby, implying that he was caught for fraud, and has to work for the HRA, which explains why he does not enjoy his work.
At the Happy Room Academy Headquarters, the player can also speak with Lyle in order to find out their current "HRA evaluation" or stop the weekly flow of evaluation letters.
It is suggested that Lyle used to be a grave-digger or fossil hunter, because if the player's house becomes the model room and has a particularly valuable fossil in it, Lyle will say that he used to dig up bones in "the yard... not the backyard, the other yard...", implying that it was a graveyard he used to dig in.
Lyle returns in Animal Crossing: New Leaf. He appears in Nook's Homes after certain conditions have been met. His office is in the bottom left of the store, where a seating area was previously. Similar to City Folk, Lyle gives the player their HHA evaluation. However, he no longer presents model rooms, a job now done by Digby. Because his office is so easy to access, evaluation letters are no longer an option.
Lyle does not appear to complain about his current job, as opposed to his predicament in Animal Crossing: City Folk.
Lyle makes a small appearance in Dōbutsu no Mori. He is seen in the background of the fireworks festival when K.K. Slider is singing on stage; he wears the same suit as his appearance in Wild World. He does not talk and makes no other appearance in the film.
 City Folk
 New Leaf
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