This looked exciting at first, but I hadn't heard about "managed accounts" and they (understandably) shift the work to the platform/API user:
Handling information requests: instead of requesting
it directly from the account holder, Stripe will request
information, such as a social security number or passport
scan, from you. You must collect this information from
the user and provide it to Stripe, otherwise Stripe may
disable transfers to the account.
