Is there an amount of money that one is chayiv to give for maos chitim? Also is it specifically for the aniyim of your city?
There is no specific amount of money that one has to give, rather the poskim say that each person has to give according to his financial capabilities. May Hashem help that in the zechus of your giving tzedakah you should always be on the giving end and not on the other side.
Chag Kasher Vsameach.