I realize my post may not have been clear on the goal; allow me to try again: I'm wondering if there are any structures (requiring < $100k and < 100 hours to set up) to pool multiple accounts such that: the trader only sees one pooled account (i.e. doesn't have the hassle of copying trades to 50 subaccounts) no person's funds are able to be withdrawn without the consent of that person (i.e. non-custodial, to provide more confidence to people considering investing their money)
You want to do separately managed accounts. You can do taxable accounts and IRAs in the same block trade. If is securities then you need RIA registration, if it's futures then CTA. Setup costs are nominal but you will face regulatory audits once in a while. You gotta ask yourself if the regulatory risks are worth your revenue.
How many investors? Going back to the investment club set up. You can be the portfolio manager, authorized to make trades but you need club permission to withdraw funds.
Thanks for the answers. I've looked into both SMAs and investment clubs, and I think an investment club is promising. The biggest benefit is the single account, which simplifies trading. At this point < 10 investors, but that may grow. After initial setup, regulatory paperwork seems manageable (Form 1065 and Schedule K-1). Any advice on the setup (make an LLC?) is appreciated.