My great-aunt and great-uncle lived this way, except they were not entrepreneurs. But, they both had well-paying jobs, and always lived below their means. After WWII, they built a modest house, and never moved from it, even when they could have afforded a much larger, fancier place. They lived in that house the rest of their lives, and eventually had no mortgage payment. They put tons into savings, and avoided going into debt; if they couldn't pay cash, they didn't buy it, including their cars.

Because they didn't have children of their own, they were able to be second parents to us, their nieces and nephews, and were generous with us. They bought me my first four cars, and paid for college for me.

After they were gone, they left an estate of over $1 million, and divided it between their nieces, nephews, great-nieces, and great-nephews in a series of trusts.

They were able to do whatever they liked, spending their money on experiences, like vacations to interesting places, and getting the newest technology gadgets (a hobby of my great-uncle), and didn't have to be concerned about money. And, both of them came from poor parents, and didn't go to college until they were grown and could pay for it themselves (they didn't take out loans to go, either).

All of the above advice makes sense. I've seen it work in the example of these two beloved people who played such large roles in my early life. They are examples to follow.