By all means share your acquisitions here, we all love seeing coins, but no one here is going to recommend that you keep buying from the kind of seller you bought this fake from and just hope that we can spot if you get duped. Stick with sellers on Vcoins, big name auction houses and eBay sellers recommended by members here(use the search, there have been a few threads on the topic). It's not always possible to spot a fake from pictures alone which is why you need to buy from dealers and auction houses that know what they're doing, have authenticated the coins in-hand and offer a guarantee of authenticity.
I think it's great that you are interested in Ancient Roman coins. If you want really high-end coins then buy from a dealer or auction house that specializes in ancient coins. If you like cherry-picking eBay, then stay with low grade bronze coins until you gain some experience. I tell newbies that eBay is a great place to begin provided you don't bid or pay more than $15 or $20 for a coin.
in this case, it's highly questionable, but ebay has an iron clad money back guarantee, even if the seller doesn't. I can attest to that. i've bought all my coins there for 15+years and got my money back on the ones deemed counterfeits by NGC which one the seller gave me my money back and the other ebay refunded me. granted, I don't buy golden ones, but they are guaranteed too.
you'd better send it to a 3rd party such as David Sear, NGC, etc. and have it looked at. as Dafydd said if its too good to be true, most of the time, it is. welcome to the ancients forum
They ONLY struck three AV Aurei types for Balbinus/ a REAL one would cost in 600K plus range. Probably less then ten exist in collections.
According to NAC, only 3 (three) genuine Aurei of Balbinus are known to exist in total. As two of them are in Museums, the coin sold at NAC 31 in 2005 (and shown above by Mikey Zee) must be the only one in private hands, as two are in the British Museum and the Bibliotheque National.