I often heard, when I was a child, my father say that the garden "is not profitable ! That's probably why he cultivated 2000m² and the orchard had around fifty fruit trees... Well, a profitable vegetable garden would almost be a tautology.
With the surfaces of housing estate gardens, often reduced to a minimum, it is not possible to set up a vegetable garden of such size and which, moreover, would be over-dimensioned with regard to the needs of the family. Let's talk numbers:with 100m², you can practically meet the needs of four people . And if you start growing vegetables, half will be enough to have fun.
As for the prices of seeds, the raw material, the association of gardeners of France offers a package of 10 varieties of seeds for 5€ ! Do not believe that the packages are empty. A quick calculation (well, not so quick anyway…) shows that with a harvest of two thirds of the number of seeds sown (72% exactly) the investment of 5€ can bring in 5000€ !
I leave you to do your experiments and your calculations. You will (may) be surprised to learn that gardening lightens the price of the caddy. And it's good for your health, but you already knew that.