Rental units are adequately covered by State laws. Sioux Falls tried to tax our landlords with a per unit tax. Why? I feel it was because they didn't have the nerve to make the slum lords comply with the laws already on the books. This tax would have driven up the costs of renting in Sioux Falls - because the landlords would not just sit back and eat the cost. Problem rentals should be dealt with on a complaint basis. The vast majority of landlords keep their properties nice. But the ones that don't should be expected to rise up to the task.
Rentals with drug problems should be exposed and cleaned. I look at a lot of real estate and I have seen beautiful antique houses cut up and rented out to questionable renters with questionable odors emanating from their units. Yet little is done to clean up this problem. A complaint basis would work better here than a tax on all properties.
This type of housing can be difficult for the renter also. Many units are crowded on a small lot with no off street parking. When this happens to a renter on a snow route there is nowhere to park their car so the snowplows can get through. Their car is then ticketed and sometimes towed. Eventually all rental units should have at least one off-street parking pad per unit.