It all depends on the price. Most supporters wouldn't be willing to risk even moderate sums on something with no guaranteed return. We know how difficult our club finds it to attract more than a few supporters to even low cost fund raising schemes.
I can't think of any fundraising schemes that have worked; certainly not at lower levels. Gillingham sold shares many years back, but it cost a small fortune to write to every shareholder, and they were in massive debt for years. Most grounds get built because someone very wealthy decides to throw their money down the drain. If there was an easy way of raising millions, every club would be doing it.