I have not heard any nicknames for people who live in Quincy. Unlike Boston, whose residents are "Bostonians," people from neighboring Quincy are not called Quincians or anything like that. Mostly, newspapers simply refer to a person who lives in Quincy as a "Quincy resident."
A person from Venezuela is a Venezuelan.
A Russian
friend
Hermit!
a gypsy!
Cantabrigian
friend
haligonian
A "Duluthian"
A person who lives in Damascus is called a Damascene.
A person who lives in Lubbock is called a Lubbockite.
A person who lives in a rented house is commonly referred to as a tenant or a renter.