Almost every apartment complex I have ever been in has followed the exact same numbering pattern.

A single building will have the floors be a letter with each unit being a number like 01 while a multi building complex will have the buildings designated as letters and will use 3 digit numbering schemes starting in the 100s. The first digit applies to floor while the second two apply to units.

If a complex has more than 26 buildings, that is when things become funky. The 27th building will likely be the AA building and it will either be the second building chronologically. Next comes BB and it will either be the 4th or 28th building, and so on.

Another thing they might do is just have those duplicate named buildings be sectioned off into a slightly more prestigious part of the property, gate it off and give it a name like Chateau @ Bronson Heights (assuming the apartment complex is named Bronson heights). If something like that is done, they will just completely restart the numbering convention.

Also, if a complex layout doesn’t seem like it makes sense while being driven, say an E next to an S, imagine it with a top down view, they likely named left to right regardless of cul de sacs, so you should have a rough idea of where each building logically should be if not chronological by drive.