contactType is not honored by xero. It will map a contact to CUSTOMER or VENDOR based on activity (invoices/bills generated).
Zohobooks
zohobook
taxNumber key will have tax registration number with respect to country. For Indian customers it will be GST Number.
Microsoft Dynamics 365
microsoft-dynamics-365
Sage Intacct
sageIntacct
Quickbooks
quickbooks
Netsuite
netsuite
Freshbooks
freshbooks
Sage 200 Standard
sage200
metaData.reference is a required field of type string (less than 9 chars). metaData.contactPersonId is required when contactPersonFirstName or contactPersonLastName is updated.