To complete COM.AR domain name registration, You will need to provide Local contact address in Argentina to confirm you are a Company registered in Argentina. Maximum of 19 characters. The NIC now state that one registrant cannot register more than 200 doamins, if they want to have more than 200 domains the registrant will have to provide documents to support their request.

Require the CUIT and Tax Code.

To complete ORG.AR domain name registration, You will need to provide
documentation to confirm you are an Non Profit Organizations in Argentina