IWe own a couple of long term rental properties in Michigan. The township they are located requires an inspection every two years in order to obtain a rental license.
They are looking to make sure smoke alarms and CO detectors are in place and functioning properly. They also want a fire extinguisher in a location that is easy to get to and visible. You need to have the furnace and water heater inspected annually ($80 a year).
I suppose they are also checking on other possible violations such as GFCIs installed near sinks and to see if the place is clean and "livable".
I don't think it's anything to be too worried about.