Reporting on top of 3 DSOs

Hi All,

We have 3 DSOs, which are getting data from FI_AR( 0FI_AR_4)  , Billing document( 2LIS_13_VCITM)  and External  data( Customer tables ) ,I want to produce report on top of them . Customer table will have KF called  Amount, every night we run batch job to post that data in SAP , based on customer number sales orders will be created  for that we will raise will billing orders and invoices .

We want to produce report based on KFs , Amount from customer table from external data , Billing amount and AR credit and debit mount from AR. The relationship between tables are M:M .

I have created Info-set on top of these 3DSOs and I have also created info cube while loading data from AR datasource  doing lookup in Billing data and customer data  but I am not getting correct data .

What is the best modelling approach  ?

Thanks

Hari