$20 is being very generous. $10 is plenty.Remember, we are not in the States. As my Jamaican friend advised me, Jamaicans work very hard for their money and have little respect for those that throw away their money. A Jamaican would only pay the negotiated price. If you are paying $50-$60 or more for one way, you are paying enough. As one who has to travel the route often, I do not want the fare to become overly inflated due to the extravagance of the once- a- year tourist. Of course, each to his own. The driver would be happy with $5 to $10 for helping with the bags. Most cafes and food shops comp the meal for the driver when he brings tourists in for a meal. Of course, if he sits with you, the establishment charges you. The driver will be rewarded later. Most drivers have their favorite place to stop and are appropriately compensated by the owner.