This isn't about the Soviet Union, but another Communist country. I recently visited China, and was surprised to see that literally every apartment window had aftermarket bars installed (and every enclosed balcony was surrounded by a cage), even 20 stories up. Apparently there are buglers that will repel down from the top of a tall apartment building, so no apartment was safe from them. On buses and public places, the locals I was with were constantly warning to be on the lookout for pickpockets and thieves on public transit.

I don't know what the official crime statistics say there, but the perception of property crime risk was certainly very high.