How to check a coach's student results when nobody will show a file

Say a prospective student is doing diligence on two coaching programs before spending $9,000. Both have testimonial pages. Both put a number on the homepage, one claiming students have done over $400 million in transactions and the other claiming 1,200 deals closed. Neither will disclose the denominator. Ask directly how many people enrolled in the last cohort and how many bought a property within twelve months, and the standard answer is that they do not share that because results vary by student effort. What can be verified independently: whether the founders own property, confirmed in county records where sale prices are public, though some states do not publish price at all and the trail stops there. Also whether either shows a complaint pattern anywhere findable. What is the actual set of questions that gets a real answer here? Nobody needs a guarantee. The useful fact is whether the median enrolled person does anything at all, and there does not seem to be a way to ask that without getting deflected into effort talk.