Several international car-rental companies, Avis and Hertz (www.hertz.com) for example, operate in Colombia. Expect to pay from COP$170,000 per day including the Loss Damage Waiver, plus gasoline. You'll get better deals, as always, by booking online. Carefully check clauses pertaining to insurance and liability before you sign a rental contract. Pay close attention to any theft clause as it may load a large percentage of any loss onto the hirer. If you rent a car with tinted windows, you'll need a special document from the rental agency that police at checkpoints will ask for. Agencies don't generally volunteer the info so be sure to inquire.