A=
ID    Date      C1    C2
X     12/01/15  A     House
X     18/04/15  B     Rent
X     21/08/15  A     Rent
Y     01/08/15  C     Rent
Y     21/12/15  C     House

B=
ID    C1    C2
X     3     House
Y     2     Rent

C=
ID    C1    C2
X     3     Rent
Y     2     House

B = pd.DataFrame(A.groupby('ID', sort = False).count().ix[:, 1:]).reset_index(level=1)