How to get Patient information for community pharmacies?

XML and business rules
1

I had working on a project for B2C Hospital:

  1. In Community pharmacies, where we cannot get patient information for all invoices. As the patient will get medicine as cash and pass by . In this case how to fill the mandatory buyer details such as ID number, address, etc… for each invoice.
  2. For hospitals, even is it mandatory to seperate simple tax and standard tax invoice. As our all customer as B2C .

Please help on this topic