The exchange rate is something like 1.77 florins is equal to one US dollar. However, there is no need to exchange money, US dollars are accepted everywhere from stores to restaurants to taxi drivers, you name it. Occasionally you might be given Aruban coins as change from a bill. You can keep it as a souvenir or ask the front desk of your resort to exchange for you...or take it to a bank for exchange...or at a casino cashier cage or if it's in a grocery store the customer service desk will change it for you back to US money. Yes, there is a bank close by where you're staying, the front desk can direct you. For 7 people you'd need to rent a van. If touring on your own is what you'd like to do by all means rent one. You can do that on-line ahead of going or wait and decide when you get there. If you're going during high season (mid Dec thru Mid April) I'd suggest doing it ahead to ensure getting the vehicle you need. The public bus is easy to use and will get you downtown or up to the high rise area on Palm Beach but not all over the island easily. You might want to consider doing a half day or full day organized tour by bus then if there are areas you'd like to explore further at your own pace then rent a van for a day or two or the rest of the week.