Being vegan isn't more expensive unless you're buying frozen meat substitutes and other processed foods. Beans, rice, lentils, and potatoes are dirt cheap and can supply all of your carbs and some protein. Add greens and other vegetables that you like. Bake your own bread. Make your own sauces and stocks. The only reason most people think being vegan is expensive is because they cling on to things that they used to eat and buy the extremely expensive premade vegan versions of them.