Symptoms of narcissistic personality disorder and how severe they are can vary. People with the disorder can:

Have an unreasonably high sense of self-importance and require constant, excessive admiration.
Feel that they deserve privileges and special treatment.
Expect to be recognized as superior even without achievements.
Make achievements and talents seem bigger than they are.
Be preoccupied with fantasies about success, power, brilliance, beauty or the perfect mate.
Believe they are superior to others and can only spend time with or be understood by equally special people.
Be critical of and look down on people they feel are not important.
Expect special favors and expect other people to do what they want without questioning them.
Take advantage of others to get what they want.
Have an inability or unwillingness to recognize the needs and feelings of others.
Be envious of others and believe others envy them.
Behave in an arrogant way, brag a lot and come across as conceited.
Insist on having the best of everything — for instance, the best car or office.