I don't know because I have't done it, but my guess is that a town car service would be cheaper. One time we took a cab within WDW (I think from AKL to CR) because we were tired and didn't want to go to Downtown Disney to transfer buses) and it was expensive for just that far (I want to say around $20). If you don't get an accurate response here I bet that you can call a cab company and they'll let you know exactly how much it would cost. You could then query a town car and they could do the same.