The seller doesn't have to pay the big fee, so the agreed price can be lower. Is this allowed? Has anyone done this in the past? Edit: Ok, I found this in Sedo's policy: What if you find the seller's info through a whois (and not on Sedo)?
What's the difference if you just looked up the whois and contacted the owner? None. I have domains listed on Sedo, and if I sell them privately, and there is no offer on Sedo for them, I just take them down. It's up to the owner if he wants to sell privately, or wait for his asking price via Sedo