In Utah County, cities typically restrict occupancy to one couple, or three unrelated singles per unit.
For example, with a legal duplex, you can put up to 6 singles, 3 per unit, or two couples total. However, there are several condo complexes just south of campus (on condo row between 700 N and BYU) and some newer complexes (like the University Ave complex , and the Lanai), that allow 4 singles per unit. The only complex that I know of that allows 6 students, is the Brownstone.
Obviously, the higher the occupancy the better the cash flow. These days, the occupancy on a unit has to conform to the original zoning regulations and cannot be changed. Unlike the past, complexes with a higher occupancy that have been built recently have had to provide off street parking for every occupant.
In the past, I’ve sold several single-family homes near campus that were zoned with a higher occupancy, and had an occupancy of 6 per unit. The problem with the higher occupancy units is that the students have to share a room, which isn’t as popular as when I was a broke Cougar years ago!
Investment note: during the spring/summer months, higher occupancy units are harder to fill, because you can find private rooms during spring/summer for as little as $150 a month per student. You’ll typically find that there is a $100 drop in rental prices during the Spring/Summer terms on most student rentals.
The best way to confirm occupancy and zoning is to have your agent (hopefully myself), make any offer contingent on your approval of a zoning verification. You can get a zoning verification at city offices for $20. It will tell you the property’s current use and occupancy restrictions.