Every One From The North is Hausa
This is like saying everyone from the South is Yoruba. There are other ethnic groups in the North apart from the Hausa, though the Hausas are one of the predominant ethnic groups. Aside the Hausa ethnic group, the Fulani ethnic group also reside in the North along with some other smaller ethnic groups.
All Hausas are Muslims
Most Hausa people are muslims, but not all of them are. There are some Hausa christians residing right there in the North, with some of them as pastors leading congregations of other Hausa christians.
Hausas are Violent
The religious fanatics amongst them are the heartless and violent ones, not the actual people of the tribe. The Hausa people are actually a friendly, warm and accommodating people. If you're doubtful, as anyone who's lived in their towns and let them tell you about just how nice to strangers they can be.
They are Not Money Conscious
This is funny because there is hardly a human being alive who isn't money conscious. What you can say about Hausas is that it typically doesn't take them having a lot of money to be content; they tend to be content with whatever money they are able to make. This doesn't mean there are not money conscious, it just means they have a modest financial culture.
They Can Never Cheat Anyone
Cheating or not cheating a person is not dependent on ethnic group, it is dependent on a person's character and personality. There are some Hausas that cheat people during business transactions, but that is because they are human beings, it has little or nothing to do with their ethnic group.
Hausa People are Dull
It is important to not underestimate the fact that the richest man in Africa is an Hausa man. A lot of people say Hausa people are dull, that they behave like cows and that is why it is easy to manipulate them into religious fanaticism, but you will be surprised at just how smart a Hausa man or woman can be. Being smart does not depend on your ethnic group, it depends on the individual.