Jacka, Benedict. Inheritance of magic series #1

"Wealth, education, resources--some people seem to exist in a glittering world on a different plane from the rest of us. Almost as if by...magic. Stephen Oakwood knows there's a magical world hidden from view. Before his father disappeared, he taught Stephen how to create and use sigls to channel power. But unlocking the full potential of drucraft takes money, power, and training. All Stephen has is a minimum-wage job and a cat. When a chance meeting leads to Stephen's skill being recognized by a member of House Ashford, everything changes. For centuries, the vast corporations and aristocratic Houses of the magical world have grown impossibly rich and powerful by hoarding their knowledge, and for a brief moment it seems as though all of that is about to be offered to Stephen. But this isn't that kind of story. House Ashford have no more interest in sharing their privileges with Stephen than they do with anyone else. What they are interested in is increasing their own power, and now Stephen's been thrust into a world he doesn't understand. To survive he'll have to take his talent and build it up into something greater--for only then can he beat them at their own game"--