Then compare all the quotes and find the best one. Keep this an apple for apple thing. If need be, discard any add-on service you don't really need, so that you can have an even comparison between quotes. Then call each of the other companies in return and ask if they can match the best offer. Using this method, you can get a discount of up to 25%.
For additional savings, ask another couple or two to ride the limo and split the bill with you. Yup, splitting the bill two or three ways is definitely one way to have huge savings on a limousine ride to the prom. The ride to the prom becomes more enjoyable with the other couple friends along.