We've met so many truly beautiful people on the tribal lands. Most of the time your own attitude will set the tone for the encounters. Be respectful and pleasant. Think before you speak. Be a peaceful person.
If there are two gas stations next door to each other and one is charging substantially less per gallon than the other, then you probably just found the border of the rez where one is paying state and fed taxes and the other isn't. Don't comment on it when you pay.
Also be aware that some tribes are still restricting travel across their lands because of covid.
Most of the year in Arizona, be careful if you book any kind of tour or anything with a specific time, because Arizona doesn't use Daylight Saving but many tribes do. When you register, look for a clock in the room or even ask for the local time so you don't disrespect them by being early or late.