First of all, whatever you buy, it must be a 4WD. Even if you don't plan on driving off-road, unexpected road closures, flooding, mud slides can all happen at any time and send you on a different path. In Costa Rica, always expect the unexpected!
On average, new cars and trucks are about 25-30% more expensive than in the United States. This is due mostly to high import taxes imposed by the Costa Rican government. Used cars are therefore much more popular but still more expensive than their United States counterparts.
The most common vehicles are Toyota, Suzuki, Mitsubishi, Hyundai and Kia, in that order. I have seen a few Ford and Chevy pickup trucks, but not many, and some Honda, Isuzu, BMW, Audi and Subaru vehicles and SUVs. By far the easiest to get parts for and maintain is Toyota, but because of this, the price will be at a premium, even for a used Toyota.
For example, a new Toyota RAV 4, 4WD is about $40,000 USD in Costa Rica as compared to just over $30K in the US. A 4-5 year old used RAV4 in Costa Rica with moderate mileage in very good condition is a little bit over $20K USD.
You can import your vehicle but it will be expensive. There is a sliding import tax scale that ranges from between about 50% and 80% of the value depending on the age of the car. The older the vehicle, the higher the tax. The assessed value will also be higher than in the United States and is not based on the Kelly blue book value, but instead is based on what the Costa Rican government thinks it is worth. Vehicles that are too old, won't be accepted at all.
If you decide to bring your vehicle, check the model to make sure parts are available. If not, parts will have to be imported. This will be expensive and take a lot of time. Just because you bring a Toyota from the US or Canada doesn't mean that it is exactly the same as the counterpart model in Costa Rica. There can still be differences between a Toyota Hilux in Costa Rica and a Toyota Tacoma in the United States, enough to be a headache.
Consider the cost of putting it in a shipping container. Containers are available in 20 and 40 foot lengths. If bringing a car pushes you to a larger container, or even worse, another container, it probably isn't worth it.
Vehicles must also be certified as safe for overseas travel, yet another headache and expense.
For us, the timing is good. Our 1999 Honda Passport with 242,000 miles and 2005 Honda Accord with 208,000 miles are too old to bring to Costa Rica and parts would be a problem. Parts for the Passport are sometimes a problem, even in the United States.
We purchased a used 2014 Toyota RAV4 4WD with about 78,000 miles on it. Through lots of networking with professionals and friends, face to face meetings and research we found Regina and Peter Herb who own Car Center Coco to find the perfect car that met all of our requirements. For a fee they will find the car, check the history, perform a mechanical evaluation, coordinate registration with an attorney, recommend and negotiate any necessary repairs and bring it to their lot in Coco for pickup. The communication and transaction was smooth and flawless. I highly recommend using their service, especially if you are moving to the Guanacaste province in the Pacific Northwest as many ex-pats do.
In my opinion, sell your vehicle before you move to Costa Rica and buy something down here, new or used. There is a lot of work and expense to bring your own car and I don't think it is worth it.