In this episode, Fred is celebrating his 40th year in business, but it was only two seasons earlier, in the episode "Ol' Brown Eyes" that he was celebrating 35 years.
Fred naturally freaks out when Lamont informs him that he could go to jail for insurance fraud if they were to keep the new furniture, but didn't seem to realize, or mind, that he was trying to commit insurance fraud by over-inflating the value of what was stolen in order to get a bigger settlement from the agent.