Yup, wiki states something around 10%+ per Chocobo being used.
Interestingly, found this in a pXI file. Definitely not related to the official game, but might have similar structures.
1st Sandy:
Quote:
CHOCOBO_PRICE_SANDORIA = 100; --Initial, and lowest possible price to rent chocobos in Southern San d'Oria.
CHOCOBO_PRICE_SANDORIA_FLUX = 20; --Amount added to base price per chocobo rental in Southern San d'Oria.
CHOCOBO_PRICE_SANDORIA_DECAY = 5; --Amount discounted per time interval since last chocobo rental in Southern San d'Oria.
CHOCOBO_PRICE_SANDORIA_DECAY_TIME = 60; --Amount of seconds since last chocobo rental in Southern San d'Oria before price decay.
CHOCOBO_RIDING_GAME_SANDORIA = 0.10; --% chance of being offered quest "A Chocobo Riding Game" in Southern San d'Oria. Set between 0 and 1.
Now lets take PJueno:
Quote:
CHOCOBO_PRICE_PORT_JEUNO = 200; --Initial, and lowest possible price to rent chocobos in Port Jeuno.
CHOCOBO_PRICE_PORT_JEUNO_FLUX = 25; --Amount added to base price per chocobo rental in Port Jeuno.
CHOCOBO_PRICE_PORT_JEUNO_DECAY = 5; --Amount discounted per time interval since last chocobo rental in Port Jeuno.
CHOCOBO_PRICE_PORT_JEUNO_DECAY_TIME = 90; --Amount of seconds since last chocobo rental in Port Jeuno before price decay.