If you are going with Virgin - they have an office in Quality Inn Lo-Q as it is known and Mears charge $6.50 per person one way.You pay Virgin and they give you slips to give to driver - make sure that you jot down reference numbers when you ring Mears and specify LO-Q as there are 2 Quality Inns on I-Drive.
We were there end of last month so prices are up to date. They must have some arrangements with Virgin as if you phone them direct they charge $14 return. They will give you 3 morning times 7.15 8.15 and 9.15 pick up and you can telephone them (2 hours notice required) for return.
We did not stay for fireworks so don't know how late the return time can be.
We found that 8.15 was ideal time as normally you get to parks just about the time they open without having to queue too long.
Eric