So I have some very bad anxiety, some bad doom thinking thoughts. I would be nervous and before even getting in part of the bid/contest I would research the seller.
But here is my other point, on Reverb I started out as a zero star review seller, I did make my profile presentable to be fair, sold three items and all those buyers gave me a fair chance and left me good reviews to help.
We all been there, using some CBT it may be a new seller we all been there, but here some acceptance Ebay takes customers sides a lot, god forbid somehow this person really gets a way with your card or money, you can always go to your bank and they work it out instantly.
Best of luck, you have the right to choose what you want. I have bad driving anxiety, before every ride I worry about parking, about bad drivers behind me, tailgaters and while still not perfect I do this CBT type thinking before every ride, even this Monk idea, basically you will get through, do not go into the deep end which is borderline OCD like every solution just think of the acceptance of "I'll handle it the way I'll handle it and it'll be right."
Either do as you feel back in the past I would avoid buying from someone with zero reviews still a bit if it seems fishy but I can tell when someone is just starting up, I bought from a lot of no sales or no reviews clothes resellers and had great luck and knew in the back of my head how to get my money back if scam.
Also agree just don't leave a review till you get it. There can be a million reasons why, maybe it is a red flag, maybe this person has other stuff they are selling and it is the holiday season they want that rating to get more views and sales. It is endless we all been there where just the oddest things happen or randomness where we doom think but sometimes people are strange as the Doors have shared...
Best of luck.