Hi Sabrina
I m not sure, the "sifu" which you are referring. Are they
Buddhist temple monk and nun or fortune teller or fengshui master.
As this term has been used loosely in the circle.
However, it is true in a certain sense, normally it is not
adviseable to play Buddhist chant at night. One need to be
selective with it as sometime spirit will be attracted to it
especially like Compassionate Mantra.
Secondly, do not be fearful of the spirit, the correct buddhist
perspective is to show compassion to them. They are in the worst
state of existence in comparison to us. In fact, as human we have
better merits than them especially you can chant Namo Di Zang Wang
Pusa. However, you need to take this a step further, you
need to have compassion like Di Zang Wang Pu Sa.
Sorry to say this, everyday you are calling on your
teacher, Di Zang Wang bodhisattva yet not practising the way
of Bodhisattva.
Some pointer to consider:
1) Will Di Zang Wang chase the pitiful sentient being out of
hell?
2) Where can they go?
The fact, he choose to stay in the hell realms to teach the
sentient being so that they can create good cause for a better
rebirth. That's act make him into a Bodhisattva.
In the same manner, you claim that there is spirit in your
house, one need to coexist with them in a harmonious way.
Otherwise, you will be laughing stock in the spirit eyes.
However, you can tell the spirit not to disturb you and
your family since you know of their existence.
The lest you can do is always dedicate the merits of your
chanting, giving and etc to them which all Buddhist do.
May the merits accumulated through the chanting be shared with
all sentient beings near and far. May all be well and happy. May
all be free from the endless cycle of suffering.
In times to come, they will become your protectors then your
freeloaders. 
see Dr Tan
webfor further reading: http://www.kktanhp.com/Spirits,Ghosts.htm
