Sellers can do whatever they want, especially since people buy their stuff for what they want to sell it for and maybe even more.
Personally, I don't ever send people offers and only buy from the people that the prices upfront and preferably a good description as well. Imo, it just weeds out some of the bullshit.....
but who am I to tell someone how they have to sell their stuff or for how much?
I just don't even try and buy from them and wait and look for somebody else... and somebody makes an offer and buys their stuff so it works out for everyone. They may not sell their stuff as quickly as they would like to because they are waiting for somebody to bid more than their item is worth, but that's their business.
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and as long as it's not a total lowball, the seller will tell you how much they're looking to get
That's exactly why I don't buy from people when they ask for offers. It feels like they are telling you how much they're looking for based on your offer and not based on what the game is really worth or even how much they secretly want for it.
It just feels shady to me, but like I said..... they can do it if they want because it's their stuff.