The best place to exchange - change money (cash) in Florence is with Carlo (or his son Marco) in their tiny shop (actually just a window you walk up to) the size of a closet that is tucked into the side of the Uffizi. They have been changing money in this spot for 40 years, and have the best rates (really!) in town. Carlo is a real Florentine and a great guy - he speaks Italian, English and Japanese - and will always take the time to share an anecdote or two. They are always just 2 or 3 pennies off the published exchange rates, with no extras, no commission added, etc., while many other exchange shops have a spread of 5 or 7 cents - and tack on a commission fee. Cash and travelers checks welcome - he will also let you charge cash on your credit card (they do take 5% on this type of transaction - but it can be really handy). He is open early to at least 7:00 PM, every day. On Via della Ninna (little street on the south side of the Palazzo Vecchio that leads to Via dei Neri if you care coming from Piazza Signoria). Follow the link below for a map.