All mod cons means all the modern comforts a home can have. A cottage with all mod cons.
It is short for modern conveniences and belongs to advertisements for property. What counted as all mod cons in 1935 was hot water and an indoor lavatory.
1phraseall mod consAll the modern comforts a home can have.
“The advertisement promised a country view and all mod cons.”
all mod cons is a phrase.
Practised in Idioms