Based on the article, ChatGPT identified five used car brands that cost the least to own after 100,000 miles. For Toyota, the AI cited engines and transmissions that often exceed 200,000 miles with routine maintenance, plentiful and inexpensive parts, and that major repairs are less common than with most competitors. Honda was praised for long-lasting powertrains, low maintenance costs, excellent fuel economy, and strong resale value that offsets ownership costs. Mazda was included for demonstrating excellent reliability since the mid-2010s, naturally aspirated engines requiring less expensive maintenance, and fewer major drivetrain failures than many rivals. Lexus was noted for sharing many components with Toyota, a reputation for outstanding reliability, and requiring fewer repairs than many luxury competitors, though maintenance is more expensive than Toyota's but significantly less than many European luxury brands. Subaru was highlighted for durable boxer engines in newer models and standard all-wheel drive, but ChatGPT added a caveat that models from roughly 2012-2014 are more prone to oil consumption issues, so later model years tend to be safer bets.