"If you're going into a luxury business, make sure you also have a second string to your bow- something you do can do that people really either hate to do or would find very difficult to do (giving a dog a bath is not that hard. Giving him a shot, shoeing horses, fixing a nasty plumbing leak, these are things that are harder to do)."Heinlein said, "A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects." Mr. Fixit's grandmother would have agreed with that: in addition to making great cabbage rolls, she also did her own cement repairs at the age of ninety. Pa Ingalls, who apparently knew how to build log cabins, dig wells, grow crops, and play the fiddle (in addition to butchering the hog), was also a sort of renaissance-man homesteader. But since most of us haven't been taught all those things on Heinlein's list, we can assume there will always be reasons we need to hire others to do the things we don't know how to do, or, as the DHM says, just prefer not to do, or don't have time to do.
And if you have skills or resources that nobody else around you seems to have, at whatever time in history you need to make some money: there's your business. There are the characters I described from Maeve Binchy's novel Whitethorn Woods. The moral of her story: if you're willing to work, there will always be people who need stuff done.
Children's literature abounds with that kind of resourcefulness too. Esther in The Endless Steppe thinks of a way to help feed her family in the middle of Siberia: she knows how to knit, although she has no idea how she will find customers who don't already do their own knitting. Then she meets a woman who can no longer knit because of a disability.
"The woman showed me the wool--barely enough for a sweater for a midget--and said the sweater was to be a surprise for her little girl, who was not well.(One can only assume that nothing like the CPSIA had been thought of in Siberia.)
"'I cannot pay you much....but I have a cow. Would one liter of milk and maybe a pail of potatoes be enough?'
"Milk? And potatoes? The buzzing [feelings of guilt] stopped. I was thrilled.
"'Could you possibly have it ready for the New Year?'
"Oh yes, I assured the lady....
"'My little girl will be so happy,' the lady said.
"That makes two little girls, I thought."