umbrella schemes

applied to a job earlier, he said yeah come in and register, armed with previous experience i asked a few things first, is it umbrella or paye etc how much is it they charge he says 15quid a week, so let me get this right i give 15quid for some numpty to take my tax and ni that must be why they call us knuckle draggers eh no thanks, any advice for what scheme lads ie umbrella paye or self employed thanks for help