You do NOT need to be an accredited investor to utilize a self-directed retirement account.
If you plan on investing in a hedge fund or private equity fund that requires accreditation, that threshold WILL still apply to your IRA.
Essentially, you can invest in real estate, startups, or any other alternative asset as long as the actual investment firm does not require accredited investors. Check with the investment issuer to see if they will be able to accept your investment.
For making your own investments without a formalized issuer, you are the manager of your own IRA LLC or Solo 401(k) Trust and must conduct the deal review on your own terms.