Replace "Master" with "somebody" and all will be clear. I don't see why the situation in the BDSM world should be any different than in any other world.

In every relationship the money situation should eventually always be adressed. Until it has been I'd say that the assumption should always be that the money is separate. ie, Who ever wanted "it" should pay for it. Since you obviously hadn't negotiated the money bit he should cough up the dough. If he doesn't I suggest telling him to politely "fuck off". Parasite boyfriends come in many guises.

I have total controll over my slaves assets.. and life. But this was thoroughly negotiated with clear pull out clouses if either party wants to break up. As soon as money is involved trust dries up pretty fast. BDSM is an adult activity, and with adult life comes plenty of boring bits that cannot be avoided if we want to keep ourselves from sticky situations in the future.