additional driver ?
 

We'll be renting from Enterprise next week. My sister will be joining us for 9 of the 18 days we have the car. Can she be added as an additional driver for just 8 or 9 of the days? Will the $15/day fee be added to my bill or will she pay them separately?

While most point of sale systems for Car Rental companies - Rental Management Software (RMS) - have the capability to charge for these daily extras for portions of the rental, these type of incrementals are usually added for the entirety of the rental. However, you should still ask the rental agent and/or manager when you rent if this is possible. If your sister is not there at the time of pick up, you will also most likely have to return to the rental office to have her added to the contract.

I just heard back from Enterprise. An additional driver can be added at any time. She & I just have to go the facility together and add her. $15/day fee.

I'd run a quote through AutoSlash...there are many contract codes for which you might qualify which will waive the fee.