Cornish Street and Eeley Close in the CBD area of Coffs I know has housing commission. Down at Park Beach there is Boultwood Street, Vincent Street, Prince Street, Arthur Street, York Street and San Francisco Avenue as well as surroundings. Over towards the Bray Street area is Kurrajong Street, Elm Street and Frederick Street which has some housing commission.
They are not all housing commission homes however there are a few in each street.
Personally, I think the Northern Beaches area of Coffs Harbour is the nicest area in Coffs Harbour i.e Korora, Sapphire Beach, Emerald Beach. Along with West Coffs Harbour.
Avoiding Toormina and Park Beach. However in both these areas you can find nice/quiet places to live, just like in nice areas they have their bad parts, like everywhere!
Coffs Harbour is fine there are no particular unpleasant streets - some areas of Toormina can be a little seedy though