None of the six options are really appropriate to my experience in paying for category listings at Sedo. I paid for a couple when I first started domaining. In retrospect the domains I tried to sell weren't going to go for very much (though I was sure they were going to make me rich). One was DronesFromHell.com, which I later sold for $9.99 on Ebay. I can't remember what the other ones were, but they were going to be single-digit sales if they sold at all.
My largest sale ever resulted from a regular listing at Sedo, but it's one that I think some companies had been watching for a long time (I'd had the domain for over 10 years).
On Flippa paying for promotions never resulted in a sale for me. The ones I sold were all regular $9 auctions.
The problem in listing free at either Flippa or Sedo is that your domain will be buried in a pile of crappy domain names. No offense, but if you're new to domaining, yours might be right at home among them
Just this morning I decided to pay $9 for a category listing at Sedo for AceVacation.com. I've done my research on this one and know it to be a fairly valuable name, where there are a lot of travel-related business with the word "ace" in their names. Still, in order for it to go for the kind of price I'd like to get for it, someone who can actually benefit from it is going to have to see it. I think it's highly unlikely that anyone who works for a travel company is going to find it while perusing sedo, because I don't think those types peruse Sedo.
I know there some "middleman" types in the domaining business. I'm curious if I can sell it to one of them, assuming it is a valuable name, at a sort of "wholesale" price. Because I'd much rather spend my time finding domain names than going through the rigmarole of selling them. So my hopes are that by making it visible at Sedo with a category listing upgrade that a middleman will see it and be willing to pay me a price that he/she can profit from.
Anyways, that's where I'm at with my understanding of domaining thus far. I'm sure a few months from now I'd tell you something completely different.