Sounds like you have a major odour problem which is a specialist subject, ozone could be an answer but needs to be used with caution, was the property damp when the housing officer returned, dehumidification can be used to remove odours as well as chemical use, urine off, other odour removers, dry wet fogging, odour seals, whatever course of action you use you need to address the actual source or sources ie thorough cleaning and removal of any solids or contaminates