Lack of advice or tools: You may miss an agent’s help throughout the process, starting with when you set a listing price. Online price calculators may not be sufficient to determine the fair market value of your home because they use completed sales, which tend to lag the market by a few months. Also, the algorithms don’t necessarily account for factors like curb appeal, landscaping, recent renovations, or school district lines.
You can also look to certain companies and organizations that have a concentration of people that may fall in the above mentioned roles such as investment companies (i.e. Charles Schwab, Fidelity), financial advising companies (i.e. Morgan Stanley, Merrill Lynch). There may be a higher concentration of people who can both afford and want to build their own custom homes or to build income-producing properties. Try linking yourself to financial advisors who may already know of people who have these types of dreams. This isn't a comprehensive answer of all the possibilities but just some thoughts. Good luck!