The first step in your car buying experience is deciding what kind of car you want to buy. While there are a lot of cool cars in Japan, the biggest factor in your total cost of ownership is the size. To save money, and frustration on Okinawa’s narrow side streets, I’d recommend getting the smallest car you can that meets your bare minimum requirements, but let’s look at the different classes of cars available.

Privately owned vehicles in Japan will have either a White or a Yellow plate. The Yellow plate is reserved for “Kei”  or “K” cars. These cars are produced almost exclusively for the Japanese Domestic market and have strict size and weight limits. They can seat a maximum of four people, and will be powered by an engine sized 660cc or less and producing a maximum of 64 HP. In the United States, you can easily find motorcycles with a larger, more powerful engine, but Okinawa is a small, slow island. The top speed is 80 KPH on the expressway. Main thoroughfares will likely be 50-60 KPH. The rest of the island is 40 KPH or less (usually less). A mechanically sound kei car will handle these speeds just fine. Kei cars may also be referred to as “A” plates as the letter “A” will appear in the license plate number to easily identify the car as a Kei car owned by someone with a SOFA license and registered through a U.S. military base.

If a Kei car is too small for your, you’ll be looking for a white plate car. White plate cars that are registered to someone on SOFA status will feature a “Y” in the license plate number. I’ve been told that “Y” stands for “Yankee” and “A” presumably stands for “American”, but I really wish the “Y” plate cars were the yellow plate cars. The white plate, or “Y” plate, will likely be either 300 or 500 series. The series is again determined by the cars size and engine size. The 500 series will include traditional compact cars, like the Honda Civic, as well as some larger vehicles with smaller engines. The 300 series includes the cars you probably want: a Nissan Skyline GT-R, Toyota Supra, Toyota Hilux Surf, dope twin turbo Subaru, Honda Accord, or that sweet, sweet, Honda Odyssey Minivan. Sadly, these cars are impractical and expensive for island life. What’s a 700 HP GT-R with a speed limit of 80 KPH and no tracks? Sad.

Your major costs will be:

1. The purchase price. 300 and 500 series plate cars in poor condition can easily be found for less than $1,000 in the lemon lot. Newer cars in good condition will sell for a fair price, though, generally less than you spend for a comparable car in the states. GT-Rs will be expensive and not in the lemon lot. Yellow plate cars generally are listed between $1,500 and $2,500, depending on condition and desirability of the car.
2. Gas. Fortunately, if you have access to a military base, you will only spend about $2.50 per gallon as opposed to 110¥ per liter (about $4.60 per gallon). Yellow plate cars, with their minuscule engines, get the best gas milage.
3. Japanese Road tax. This tax must be paid annually and will vary depending on the size of your vehicle.
4. Shaken. Shaken, or Japanese Compliance Inspection (JCI) is a biennial inspection to ensure all cars on Japanese roads are safe, maintained, and do not have any illegal modifications. You will pay a vehicle weight tax, compulsory insurance, a processing fee, and pay for any repairs necessary to bring your car into compliance. The JCI is tied to the car, not the individual. If you purchase a car from the dealer, the JCI will generally be completed before you receive the vehicle. If you purchase from a private seller, the JCI expires 2 years from when they last completed a JCI inspection.
5. Insurance. As an American, you will be required to purchase additional insurance on top of the insurance paid for as part of Shaken. 

Below is a rough estimate of how much you could expect to pay:

Car	Gas (Annually)	Road Tax (Annually)	JCI (Bi-annually)	PDI (Annually)	1 Year Cost	2 Year Cost	3 Year Cost
Kei (Yellow Plate)	$500	$30	$200	$200	$730	$1460	$2390
500 Series	$1000	$ 75	$300	$300	$1375	$2750	$4425
300 Series	$1500	$180	$400	$400	$2080	$4160	$6640

If you have a family of five, you’d struggle to fit in a Kei car with a maximum seating capacity of four. Whatever your situation is, I’d recommend getting the smallest car that can accommodate your needs.