1. *Cancellation Fees*: Many rental companies charge a fee if you cancel your reservation within a certain time frame before the scheduled pick-up. This fee can vary, so it’s essential to check the specific terms of your reservation.

2. *Full Refunds*: Some companies may offer a full refund if you cancel your reservation a certain number of days or hours before the pick-up time.

3. *Non-Refundable Reservations*: Some discounted or special rate reservations may be non-refundable. This means that if you cancel, you will not receive any refund.

4. *Partial Refunds*: If you cancel within a certain period, you might receive a partial refund after deducting a cancellation fee.

5. *Changes to Reservations*: Some companies allow you to change your reservation without any fee, while others might charge for changes.

6. *Prepaid Rentals*: If you prepay for your rental, the refund policy may differ. Some companies might offer a refund minus a cancellation fee, while others may have stricter policies.

7. *No-Show Fees*: If you do not show up to pick up the car and do not cancel the reservation, you might be charged a no-show fee, which can be the full amount of the rental.

8. *Third-Party Bookings*: If you book through a third-party website or travel agency, their refund policies may apply, which could be different from those of the rental company.

9. *Insurance and Add-Ons*: Refund policies for insurance and additional options like GPS, car seats, or additional drivers may also differ.