If you are able to trade electronically with someone then you are, in what ever manner is appropriate. It could be full B2B integration or it may just be receiving a spreadsheet. Some may call ERS: self-billing or buyer-generated-invoices.
10. Minimal number of vendors / customers / stock / materials / etc. applicable to process
The master data files are regularly reviewed to ensure that only those master files that are used are active in the system. There are minimal duplicates, unless for a specific reason, and there are controls over who can create / maintain master files.