GST Calculation using third party integration

[Former Member]

Experts,

We are on older version of SAP - SAP 4.7 and SAP CRM. Currently there is no plan to upgrade SAP systems. So we understand that GST related notes that are planned to be provided by SAP will not really be available for us.

Additionally there are three major non SAP ERP systems that are operational with us.

In light of this, we are planning to evaluate a third party tool that would be capable of computing GST (with applicable 3 components of SGST, CGST and IGST with necessary offsetting etc) and also generating returns from compliances perspective.

Request your help on:

1. Whether Substitution will help in routing all line items coming up for financial postings in R3 to 3rd party system?

2. Whether thru substitution we will be able to route all billing line items coming from CRM system for postings in R3?

3. Any clues on how to go about writing substitution?

4. We have standard Doc Type RV for billing with some defined Transaction Types. So believe substitution needs to be written for Complete Document. Overall we need to 'pause' some defined entries (like few Doc Types + Transaction Types) coming from CRM, pass entries to 3rd party system, come back to R3 with taxation values and carry out financial postings in R3.

Please help with your thoughts.

Thanks in advance.

SA