A chinchilla will pee anywhere and everywhere depending on where the chinchilla is.
If you keep the chinchilla mostly in the cage then it will only pee in the cage and not everywhere since it will be in the cage.
But if you let the chinchilla out to roam around the house then if it needs to pee then the chinchilla will pee on the floor or wherever it is.
A chinchilla will also spray their urine to tell someone to back up, back off or to inform you that they feel threatened.
Chinchillas also like to chew and gnaw on things as well so if you let the chinchilla roam around the house it can cause damage.
I love chinchillas myself but I wouldn't want one as a pet though.