Trading/Auctioning High Valued Items

I'm not too familiar with the Trading/Auctioning side of Neopets but I have a stamp that I'd like to sell and was wondering if any of you had some tips to make sure that I make a fair deal -- well, tips for trading/auctioning in general too. The stamp is an Island Acara Stamp - Retired & rare. The lowest on the trades right now is asking for 30 million. I'm hoping to get 29 million or as much pure np I can for it plus ets items. Now, from what I understand, even if I set up a private auction the max they can bid is 20 million? What is the best way to ensure that I would get the other items/np & not get scammed? Get the extra items/np before I set up the auction? Any help would be appreciated! :)
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Some sellers put junk auctions maybe worth 15M each or lower and the buyer can bid on all of it depending on the price already negotiated. WOW! Selling: Maps, Neggs, Stamps, Coins, Cards, ETC! http://www.neopets.com/browseshop.phtml?owner=1434sweet#p
WOW! Selling: Maps, Neggs, Stamps, Coins, Cards, ETC! http://www.neopets.com/browseshop.phtml?owner=1434sweet#p

When I sold my Candychan Stamp I asked for ETS BD items. I didn't trust doing multi auctions. Some buyers tried to bully me into doing auctions but I waited for someone who would trade in items. Good luck =)

[quote=melaka]When I sold my Candychan Stamp I asked for ETS BD items. I didn't trust doing multi auctions. Some buyers tried to bully me into doing auctions but I waited for someone who would trade in items. Good luck =)[/quote] This is the best way of doing it.. just get them to offer multiples of PCC, SOS or Gbomb.. those items are really easy to sell afterwards. Sometimes I have ended up selling the weapons back to the same person for pure.. so that the trade ends up being just about pure neopoints. :P