I would never consider using a taxi for that distance, but we can take an educated guess. From Cannes to St Paul de Vence is about 30 kilometers or nearly 19 miles. Since the taxi is unlikely to be able to get a fare coming back to Cannes, he/she would probably refuse to do this on the meter since this would involve a nearly 40 mile round trip. Its hard to imagine anyone doing this for under 100 Euros, but its just a guess. And you would still have the issue of getting back to Cannes. You could try to negotiate to hire a taxi for the day (or half day) but you are probably talking at least 200 Euros. The last time we were in Cannes (this past December) we tendered in early in the morning off the Brilliance of the Seas. As is typical of this part of France, there was not a single taxi in sight (it was Sunday morning and they were all probably sleeping). One way to save some taxi money would be to take the train to the Cagnes sur Mer station (just west of the Nice Cote d'Azur airport) and try to get a taxi from the station (the closest station to St Paul de Vence). From there its only 8 kilometers (about 5 miles) and there is also a public bus that makes that trip (its across the street from the station and you could ask for someone to point out the bus stop).