Finra arb is not your typical arb. You don't get to go infront of a retired judge and state your claim. With Finra you will sit infront of a panel of three. I don't know if I would want to do that without an attorney. In my wirehouse days it would cost a firm 20-25k in my area to go to arb. The general rule of thumb was if a client had a serious true complaint, the firm would settle and screw over the rep under 20k. Also, in arbitration, if you lose the other party can ask the legal expenses be paid out by you. Just know the risks involved if you are going to try to file pro se.
I forgot to add my disclaimer. I am not an attorney, but I once did stay in a hotel that was down the street from a Holiday Inn Express
There is a procedure where you can waive rights. You can let them decide if the money is minimal. It costs, if I remember, a buck fifty, and you get it back if you win and don't go thru it. It's on the web site, and they'll help you. They are very sensitive about this stuff. I think you'll win if you can document your conversation. Do it. Or I'll be pissed. If they do it to you, they''ll do it to others. Show them somebody out there has balls (unless, or course you 're a female). But if you're a pre - op, show 'em!!!!
It sounds like flytiger has done this before pro se. Maybe you should PM him for more details. I have only seen larger complaints in my limited experience. Good Luck