I've used Prince Limo
http://www.princelimousine.net/ dozens of times. The owner, Stephanie, is always right on top of things and has always worked with me to find the best solution for my needs.
One of the first times I used her service to take me from Logan up to my condo in Laconia, I was coming back on a Friday night from a 5 day business trip and called her to say I needed a car. She shows up herself, with a stretch Lincoln. I asked her if that was a bit excessive for 1 person... then she tells me that because it is a stretch and has a partition between the driver and passenger compartment, I can have open containers in the back. And, wouldn't you know it, there was a cooler full of Heineken for my ride.
Giver her a call, I think you'll be pleased with the service.