I believe it is a bit too early to book now for the year end. Current prices for a pick up Nissan 4WD at national are 500 US$ a week insurance included and unlimited mileage. These are diesel engines , low comsumption and fuel is much cheaper than gazoline. National has a franchise of 5000 Dominican pesos i.e 300 US$ despite their ' full insurance scheme '. Althought you may get your rental contract at the airport of entry , ask for a ' normal contract ' you will avoid to pay approx 50 US$ of airport fee. Pascal
