Our limo company adds in 18% gratuity, so actually our driver loses 2% of what he would have gotten had we had the choice to tip on our own. A 120.00 tip for 24 hours worth of work is not above and beyond. I feel that it's fair.

If you or your company can afford to hire a driver, then of course you can afford the tip. For someone who hires a driver this must be mere chump change!