I recently moved to Bismarck from Toronto. Prior to Toronto, I've lived in Dallas, Las Vegas, Atlanta, and Oklahoma City. One of the first things you'll notice about Bismarck and most other ND communities is the nearly complete lack of "bad" parts of town. There is no poverty or crime here relative to all other places I've lived. So, you'll feel very safe where ever you live in Bismarck.
There are plenty of new apartments here as the population is growing. Most seem to concentrated on the North side of the city. I have several friends who live in the Cottonwood Apartments. Here's the link:
IMM Apartments: Over 5,000 apartments for rent: Cottonwood Apartments
They are nice and seem to be well managed.
Another big difference I've seen in Bismarck apartments versus other places I've lived is the lack of amenities. You won't find pools, tennis courts, work-out rooms, and most don't have club houses. Some do --but most do not.
I would highly advise getting an apartment with a garage if you can. They are a little more expensive, but in the winter, you'll be glad you did it.
I live in an apartment managed by Goldmark. I have not had any problems and the apartment is nice. The rules are a little strict. But, I think that helps keep the apartments a little nicer.
Personally, I don't care for the area near the Kirkwood Mall. Apartments in this area are older and not in good repair in my opinion. Apartments near the river are variable. Some are nice and some are not.
Good luck.