If you are unsure if you have a single-property account or a multi-property account, then there are a couple of ways that you can tell.
1) When you go to Residents:
If you see the menu option for "Units", then it is a Single Property Account.
If you see the menu option for "Properties/Units", then it is a Multi-Property Account. 
2) After selecting the appropriate option mentioned above, you will have access to view your units.
Single Property Accounts will immediately display the units registered to the account.
Multi-Property accounts will display each property registered to the account. After selecting a property, it will show you the units registered to that property. 