Coach wants 20% of my first duplex for "walking me through it" instead of a flat fee

Those two options aren't the same product wearing different price tags. The $4,000 is a coaching fee, meaning you pay for teaching and you keep everything you build. The 20% version makes him a partner in a specific property, meaning he owns part of the thing and you're stuck with him after the teaching ends. People use "coaching" loosely for both, but the strict line is whether the person has an interest in your deal or only in your tuition.

On licensing: in most states, being paid a fee tied to someone else's real estate transaction for services like negotiating or procuring a buyer is what triggers a license requirement, and where the line sits between "teaching" and "acting for you" varies state by state. That's a question for a real estate attorney in your state, not a Facebook group, and it's worth one hour of their time before you sign anything.

"Figure out the paper later" is the part I'd sit with. 20% of equity has to live somewhere: a 20% membership interest in an LLC, a recorded deed interest, or a note against the property. Each one behaves differently when you refinance, when you sell, when he wants out, or when he stops answering the phone. Ask him now, in writing, which one he means, what happens if you want to buy him out in year three, and whether he has a say in your decisions or just a share of the money.

One thing the incentive story hides: a partner who only gets paid when you close has a reason to tell you the $260,000 duplex works. A flat-fee coach can say don't buy it.