At the end of the day, it all comes down to ROI. If this had a good ROI, it probably already attracted enough investors without needing to create such a investment product. If not, then I might as well buy SP500.
It might be useful to think of Legends Solar panels as a kind of fixed income security. It depreciates over time but produces a steady stream of dividends. Significantly lower risk than the stock market, but with somewhat predictable returns. The important thing we hope to capture is the experience... it'll feel much more like owning a consumer product than an investment.
Similarities include physical depreciation, need for maintenance, insurance, importance of location, vacancy risk (vs bad weather), tenant risk (vs power customer), how each case is special snowflake, etc.