I know we all have our own family smells!
The house we are buying has a very STRONG smell. Partly the 4 big old dogs and 3 cats I suppose and maybe some cooking smells on top. It is quite unpleasant. They have the heating on very high when we go round too and are quite elderly and there are old carpets everywhere and.... you get the picture.
We will rip up carpets as soon as possible. Anthing else?
The rented house we are in at the moment still smells of 'other people' after 9 months. Maybe it's the carpets.
Not fond of spray fresheners or plug ins but will go with whatever you think works!