I've been saying this for years, telling my customers for years and using it for years but it's always nice to see someone else mention it. Buying 10 year old cars and maintaining them is the cheapest way to own and operate a car. Look at the graph from Reddit, especially the black dots:
The reason for this is that depreciation, interest, license tabs and insurance costs are silent killers. They add up to thousands of dollars per year and you don't even notice it.
Now, I would go one step further and say that buying a mint condition 12 year old car from the original owner who has all the maintenance records, is going to be by far the cheapest option, but 10 year old cars aren't bad either.