LIVELIHOOD
live off the fat of the land
to grow one's own food; to live on stored-up resources or abundant resources.If I had a million dollars, I'd invest it and live off the fat of the land.I'll be happy to retire soon and live off the fat of the land.Many farmers live off the fat of the land.
live within one's means
to spend no more money than one has.We have to struggle to live within our means, but we manage.John is unable to live within his means.
someone's bread and butter
someone's income; someone's livelihood—the source of one's food.I can't miss another day of work. That's my bread and butter.I like to go to business conferences. That's good because that's my bread and butter.