Your transfer corporation will validate this along with you when you make your reserving. Gratuities usually are not included in the price, so it is at your discretion as to whether you want to suggestion your driver. If you're from the US, it is customary to suggestion your driver 10-15%. https://punta-cana-excursions77542.blogsvirals.com/30291387/punta-cana-excursions-an-overview