ArcGIS For Desktop 10.3 includes a new Single House Subaddress style that you can use and map the unit info in field A to the SubAddrUnit component when you build the address locator.
The subaddresses for multi-unit occupancy can be stored in 2 sets of elements – Building type/Building Unit (optional), and SubAddrType/SubAddrUnit. These components can be used for any 2 sets of subaddress components if users prefer, for example, Level 4 Unit 21, or Terrance C Door 6. It is common that only SubAddrType/SubAddrUnit is used to support simple unit information such as Apartment 101 or Unit A.
Building Type (optional) – Building Unit (optional) – SubAddr Type – SubAddr Unit
Examples: 30 Pecan Dr Block B Unit 105
5 Gilman Ave Apt 17
There is a bug that has been confirmed with this new Address locator as per the below thread:
Will this bug be fixed with the release of 10.4 in first quarter of 2016?
Unfortunately, we were not able to complete fixing this issue for the 10.4 release of the software. We are currently working on resolving the issue and target fixes for the next available release of the software.
I am hoping for the same!
We are currently using the locator you mentioned in Geocoding Addresses with Apartment Units
But that post has so many locator versions uploaded to it, I found it difficult to determine which one to use...
I really hope this becomes a priority...