Yes, one time registration is required for each bill type to access the resident portal. You need to register for each bill type and account you wish to pay online. If you own two parcels, you will need to register both parcels. Once the initial registration process has been completed for each of your accounts, viewing and paying future invoices will be in place.
If you register your accounts with the same email and password, you will get a list of accounts to choose from in your customer portal.