While the opportunity costs are a somewhat substantial risk that Richards faces with his product and company, ultimately the biggest risk of all is determining which business model to follow.  There are four basic business models and all have their own associated risks: sell his idea, licensing his idea, outsourcing the production, or the crawl-walk-run strategy.  His decision on which method to follow is likely a critical determining factor of success so he must be concerned with several factors which include profitability, leverage, success probability, and exit strategy.
The first business model is to sell the idea which would be the least profitable option; however the exit strategy is concise and obvious.  This option is also the least risky of the four business models because Richards would have enough of his own money to pursue this option and therefore would not need angel investors.  It is unlikely however that Richards will be able to get anyone to pay what he thinks the idea is worth.  While the risk is low and exit strategy clear, the profitability would be minimal in comparison to the other business models.
The next potential business model is to license the idea with the hope of Richards receiving a payout up front as well as royalty payments per unit sold.  There is a large amount of risk involved with this as Richards lacks both business connections and expertise in regards to contractual/licensing agreements.  Obviously this option would have more profitability over simply selling the idea; however profitability would likely be greater if Richards were to manufacture and sell the product himself.  While this option involves a little more risk and a little more profitability, Richards must be aware that the higher the risk the higher the potential payout.  
The final two business models (outsourcing and crawl-walk-run) involve much more involvement on Richards’ part and potential increased profitability, thus more risk.  The outsourcing production model would probably require more refined expertise from investors since Richards is lacking in that area.  This model provides for no guarantees, and also increased associated opportunity costs.  Richards would be in charge and would therefore have to determine the methods of distribution and effective marketing tactics.  The exit strategy with this option is also unclear but is critical to the success of the O-Fold and whether or not potential investors would be interested.  When investors enter the picture, they will need to know what their return on investment will be as their decision will be based on the attractiveness of the offer.  Also, the exit strategy is not clear in this model so Richards would need to determine the expected exit strategy prior to going to investors.
Lastly, the crawl-walk-run strategy involves much risk but ultimately the most attractive (potential) profitability.  A management team would need to be comprised to run the operations and to arrive at a simple means of distribution (i.e. internet sales via company website).  While Richards will personally take on all the risk in the crawl stage, he is more likely to entice investors with actual sales and market data on the product for future stages.  The investors would likely be needed in the walk stage when the company will expand; at this point a patent will be needed, methods of production, marketing ideas, and distribution channels.  Finally, if they got to the run stage where they were producing and selling large quantities of O-Fold they could be confident in the fact that the risks they made were all worth it.  The exit strategy would simply be to sell interest in the company or to sell the entire company outright.
