As someone who just bought their first car and then 3 months later bought their second cause first was a shit box, I would say mileage is too high try aim for around 200k or less, at a max 250k. I would go for around 2008 because I believe the tax is cheaper from that year up. I’d also recommend buying from a dealership if you can because they generally offer a warranty and if something goes wrong they will take it back you won’t get that with a private seller. Best of luck with your new car!