Despite OP would not find any sympathy on the forum about his lost money it could be a great example for all not experienced newbies to not fall in these types of scams.
No matter what: carding forum, a super deal for iPhone (50% cheaper or even 70% if bought in bulk 5 - 10 pieces), Paypal and Western Union transfers, accounts with money for 50% less and so on.
As we can see, OP did all that was possible to check the forum and the deal he made, anyway, he was scammed not only for the initial 500$, but they managed to get additional 200$ from him.
These are already well-known scams, but I can imagine that newbies can still fall into these because a lot of them are really unprepared for something like this. These forums look 100% legit and everything is mastered to the last detail.
There were a few of such "established" carding forums in the past, which offered carding services and had marketplaces with carded cheap equipment, but very soon they turned out to be full scam when they realized that there is a lot more money to be made from scamming not experienced scammers (forum users) as from managing a "genuine" carding forum.
Of course, all of these forums now are 100% fake, especially if one has found them with no problem using Google
. Believe me, legit carding forum would be very deep hidden in the dark web, accessible only via TOR with full communication, messages encryption, only accessible via invite link from already established long time members.