How many games have you played?
About 20-30.
How does someone get that much money? Do you sell any big name player you happen to sign/get in packs and only play matches with lower value players?
Also, has anyone tried selling the 99 match contracts? Are they big earners?
Buy-low sell-high with consumables. Contracts, fitness, healing, chemistry. Make about 300 on each transaction, enough of them add up. Had a couple of players I've bought and made a few thousand on (Sanchez in the space of 30 minutes the other night, for example).
No, they didn't appear to be going for much. I made a fortune on contracts last year but it seems a lost cause last year. If you have 10 managers in your club, all with +3%, then when you apply a contract the (10x3%) will apply extra games to that player, so contracts are less important.
Also with several consumable duplication glitches in the past week, people have overpopulated the market with them, selling dirt cheap (as it's all at a profit) and the market is going to take time to get back to where it was, if it ever does.
I've probably got another 250k worth of consumables to sell when prices go up a bit (fitness and hunter chemistry cards).
EDIT: 99 contracts weren't going for much to start with, but with so many duplicated ones and no ability to search for just 99 contracts, I doubt they'll go for much.