GST - Setup IO vs OU

Hi,

We are implementing GST for a business where because of the nature of business, the client has more than 300 subsidiary companies across different states. The client has applied for a GST registration number for each of this companies and will be filing returns for each of this separately. Currently these companies are not mapped in the Oracle. The magnitude and volume of transactions in these subsidiary companies is less so the client manages these outside the system.But in the post GST environment, the client wants to map all these companies in Oracle so that all the data is readily