Graduate or professional students and non-traditional students are likely to be a lot less risky and rowdy compared to traditional undergraduate students.
Be careful about profiling characteristics. Use of some characteristics constitutes illegal discrimination, and state laws may have more protected characteristics (example). It may be best to ask a lawyer familiar with housing laws applicable to the area about what is and is not illegal discrimination in the area. Note that non-traditional student status is commonly defined by age, veteran status, and/or marriage/family status, all of which can be protected characteristics, so that would be something to ask a lawyer about.