Okay, I admit I love private drivers and private transfers. No wasting time trying to find our way around in a rental car. That is no fun, especially for the driver. I repeatedly hear how stressed out they are each night worrying about driving the next day on unfamiliar roads in unfamiliar countries. Some people think that is an adventure. Many have learned that is a nightmare.
When I step off a transatlantic flight all I want to see is a sign that says LEWIS. The local driver whisks you away from the airport and directly to your rental. No muss, no fuss, no stress, If at least 3 people are traveling together the cost is almost the same as taking the airport train, switching to a cab at the terminal, lugging your luggage, etc., etc., miserable when you are so tired. Or worse yet, trying to find your way out of the airport terminal and to your accommodations in a rental car when you are exhausted. Yuck!
We usually hire airport transfer drivers for airports and a private driver guide for sightseeing 2 days out of each week of our stay. We use the bus and cabs for local transport and a private driver for day trips further afield. For example while staying in the Cotswolds we used the driver to take us to Wales, Glastonbury, Gloucester, Winchester, Windsor, Bath and several other places. In the Scottish Highlands we used a driver to take us to the Isles of Skye, Mull and up to Applecross with a bunch of places in between. In Italy I have used drivers all over Tuscany, Cinque Terre, Amalfi Coast, in and outside of Rome. It is usually a 9-10 hour day and the driver plans our route to see as much as possible as comfortably as possible.
PLUS you get to see a lot of places no other tourist sees because you are with a local that knows the area. He wants to be sure you have a good time. His mission is to take you where you want to go as well as showcase his home country along the way. And they love showing you little known gems.
Drivers can be pricey if only two people are traveling or the exchange rate is poor, so use them sparingly and make sure the driver knows what it really important to you so he can plan the most expedient route. Expect to pay 350-450 pounds per day in Great Britain, 400-500 euro in France and Italy. Divided by 3-5 people (since they charge per car not per person) makes it much more affordable and is the perfect way to see a lot in the least amount of time.