We can highly recommend the below company for Orlando car rental.
US Car Hire can provide rentals in any location within the USA and they offer excellent service at very competitive prices.
The rental will be with Alamo or National (your choice) and if your rental is over 8 weeks away, you only need to pay $35 to secure the reservation.
Once you have made your reservation, you will receive a pre-paid voucher. You can also register for the Alamo Express Service which means you can avoid the lines at the car rental desk and use the fast service kiosks instead