A more fundamental problem is that a new FTO, even when run on a commercial basis, is more likely to make a loss during the first year. With good management and lots of luck it may break even during the second year, and hopefully make a small profit during the third. All of this assumes that things like economic downturns don't get in the way.
So after the first year when the company has a loss of one hundred thousand or two hundred thousand pounds on the books (even more if you bought the aircraft instead of renting them), who is going to want to buy a share in it?
It would be far less risky to simply pay a conventional FTO to do your training, even if you were daft enough to pay up front!!