Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

Administrator vs Broker vs Custodian for a Solo 401(k)?
Their paperwork should help you along.  Schwab is the broker and custodian, you are the administrator.  There's virtually no paperwork after the account is opened, until you hit $250K in value, and then there's one extra IRS form you need to fill out each year.  See One-Participant 401(k) Plans for a good IRS description of form 5500. Disclosure - I use the Schwab Solo 401(k) myself, and the only downsides, in my opinion, the don't offer a Roth flavor, and no loans are permitted. Both of these features would offer flexibility.