Qatar is safe as houses. It's Johannesburg that can be a war zone. Not on the Beirut/Baghdad scale, but still. They frisk you for guns at the nightclubs and when you're clean, they give you one.
Latest crime (reported) statistics for SA announced yesterday. Search the SA press for details. I'm not trying to put you off or scare the living daylights outta ya, but a greedy landlord and a greedy armed robber are two different kettles of fish.