Owning an older car in Japan is pretty much the same thing as owning a 3 year old car. 5 or 6 years ago, it was slightly different as cars older than 10 year old had to pass an extra test. What happened was that you had to pass the mandatory technical inspection (Shaken) every 2 years, but every 2 other years, you had some kind of a mini tech-inspection to pass in order to make sure your car was still in driving condition. It was cheap and took 30 minutes at worst. Now the secondary inspection doesn’t exist anymore and you only have to pass the main one every two years like all the other cars. Taxes are based on car and engine size. Cars over 10 years old have to pay an extra 10% on their biennial taxes though , which is hardly a deal breaker (an extra 25 to 100 USD every 2 years).