...as far as I'm concerned, the less people involved the better--the idea that there is someone outside waiting is sort of a turn off.  Plus, the whole driver thing can bring up notions that you are affiliated with either an agency or a pimp--even if you aren't.

I live alone in a large house on the end of a cul-de-sac.  My neighbors are very nice and watch my home while I am out or on business trips.  

They also know who comes and goes.  Strange cars, especially ones that are occupied will get noticed instantly and draw unwanted attention to my trysts.  I avoid anyone who uses a driver like the plague.

HPG

I worked with an agency for a few months, so I've had the experience of having a driver as well as working entirely on my own.  Yes, it's convenient to have someone else driving, (especially when so many clients will offer drinks!) but the downside is that you tend to be more tied to the clock when someone's waiting for you.  As the other responses suggest, it's also bad PR, and why many people will avoid agencies altogether.  There's nothing like a carload of girls driving up and down the street to get the neighbours' talking!  I think you have to look at it from the client's point of view here, and in their shoes, I'd avoid SPs with drivers too.

Try mapquest to find your addresses, it's gotten me all over North America!

-Anya

Fatima,  I have the solution for you.  GPS...  I just gave my wife a Garmin SPIII and she loves it.   Before, she couldn't find her way out of a paperbag and now she is a power driver.  Though they retail for a grand, on Ebay you can find it substantially cheaper.  Check the web site.  Easy to use.  You will never get lost.