It is the purpose of this chapter to assure that rental housing in the city is decent, safe and sanitary and is so operated and maintained as not to become a nuisance to the neighborhood or to become an influence that fosters blight and deterioration or creates a disincentive to reinvestment in the community. The operation of rental residential properties is a business enterprise that entails certain responsibilities. Operators are responsible to take reasonable steps as are necessary to assure that the citizens who occupy the units may pursue the quiet enjoyment of the normal activities of life in surroundings that are: safe, secure and sanitary; free from crimes and criminal activity, noise, nuisances or annoyances; free from unreasonable fears about safety of persons and security of property; and suitable for raising children.