Alexander lives in an apartment building and gets a $250 benefit from playing his stereo. Mary, who lives next door to Alexander and often loses sleep due to the loud music coming from Alexander’s stereo, bears a $350 cost from the noise. Mary would like to offer Alexander some money to turn down the volume on his stereo. If Mary had to hire a lawyer to draw up the contract, what is the maximum amount she could pay to the lawyer to ensure that both Alexander and Mary would benefit from the agreement?