the royalty bearing fee is 99 then you need to pay epic 2,500 and after that you need to pay them 25% of the profit.
A team creates a game with UDK that they intend to sell. After six months of development, they release the game through digital distribution and they earn $15,000 in the first calendar quarter after release. Their use of UDK during development requires no fee. Upon release they would pay US $99.99 for a Royalty Bearing license. After earning $15,000, they would be required to pay Epic $2,500 ($0 on the first $5,000 in revenue, and $2,500 on the next $10,000 in revenue). On subsequent revenue, they are required to pay the 25% royalty.
Its actually not that bad if you end up making over 15 thousand but If the game is just on a dead site and no one buys it you will actually lose money.