A little long and OT, so skip unless you're interested in the Collectibles Market.
The Collectibles Market is not for the faint of heart. For every guy like this, who buys low and smart and hits the market with a winner, there are dozens who have not done so well...but this guy sounds like he might be set for life if he really has the inventory of Brady memorabilia that he claims to have.
Looking back, it always looks easy. But, who knew in 2011 (when he apparently started buying Brady stuff) that Brady would go to four more SB's and pick up two more Lombardi's?
It's interesting that this was sold before Brady lost last Sunday. So, this guy isn't greedy. The Collectibles Market fluctuates wildly and auctions are a real crap shoot. He sold when 28--3 was on peoples' minds. He decided to take his profit and possibly forgo more money because he didn't know what would happen if Brady lost last week. My guess is he would have pulled the card from the market and waited before he tried to sell it again.
A friend has his own store where he sells a wide range of collectibles. The fluctuations in markets are nerve wracking. Verified autographs by all four Beatles on a scrap of paper are probably worth $10,000 today; the same signatures on a high quality photo will get nearly $20,000; on an original Album Cover in good condition (not on pieces of paper at the bottom)? $40,000+. John Lennon's autograph on a piece of paper? $5,000. On an original Album Cover in good condition? $15,000.
Unless he wins another SB, the market for Tom Brady memorabilia will probably never be hotter than it was after LI. It's not rational. Also, he doesn't sign a lot of stuff, so the value will probably always be there.
The Beatles, when they were together, signed relatively little. They became popular so quickly that they didn't have to send out hundreds of promotional photos.
Then, John's premature death made anything signed by the four of them on a quality medium become instantly collectible. Also, most "Beatles" autographs that you see online are either frauds or were signed by one of their assistants. And, they signed a lot of stuff after concerts that is low quality and sloppy. My friend is a recognized authenticator of Beatles' signatures and he said that most of what comes to him is fake.
The Gold Standard for authenticated signatures, which never go down in value? George Washington, Marilyn Monroe and Babe Ruth. Washington sigs are very rare (Lincoln actually wrote a lot of letters and signed a lot of dispatches during the Civil War, so his sig isn't as valuable...will still get over $10,000). Monroe signed very little. A lot of Babe Ruth autographs were for fans who lost them.