Option 1 : 3 days 2 nights
Day 0: BUF --> PHX --> Tusayan AZ lodge for rest
Day 1: Tusanay --> South Rim Top --> South Kaibab Trail --> Backcountry Office --> Inner Gorge --> Phantom Ranch or Cottonwood Campground for rest
Day 2: Phantom Ranch or Cottonwood Campground --> North Rim Top --> Lodge for rest
Day 3: North Rim Top --> North Kaibab Trail --> Inner Gorge --> Bright Angel Trail --> South Rim Top --> PHX --> BUF
Option 2: 2 days 1 night
Day 0: Buffalo --> Sky Harbor International Airport, Phoenix --> Tusayan AZ lodge or South Rim campground for rest
Day 1: Tusayan or South Rim Top --> South Kaibab Trail --> Inner Gorge --> North Kaibab Trail --> North Rim Top lodge for rest
Day 2: North Rim Top --> North Kaibab Trail --> Inner Gorge --> Bright Angel Trail --> South Rim Top -- > PHX fly to Buffalo
Day 0: BUF --> PHX --> Tusayan AZ lodge for rest
Day 1: Tusanay --> South Rim Top --> South Kaibab Trail --> Backcountry Office --> Inner Gorge --> Phantom Ranch or Cottonwood Campground for rest
Day 2: Phantom Ranch or Cottonwood Campground --> North Rim Top --> Lodge for rest
Day 3: North Rim Top --> North Kaibab Trail --> Inner Gorge --> Bright Angel Trail --> South Rim Top --> PHX --> BUF
Option 2: 2 days 1 night
Day 0: Buffalo --> Sky Harbor International Airport, Phoenix --> Tusayan AZ lodge or South Rim campground for rest
Day 1: Tusayan or South Rim Top --> South Kaibab Trail --> Inner Gorge --> North Kaibab Trail --> North Rim Top lodge for rest
Day 2: North Rim Top --> North Kaibab Trail --> Inner Gorge --> Bright Angel Trail --> South Rim Top -- > PHX fly to Buffalo