If you want to know how many apartments are in a given building and not the whole complex, don't ask how many apartments are there. I'm not in the habit of memorizing the exact number of units in an entire complex. If you want to know whether a building has brick on the exterior, don't ask if it's made of brick. I didn't build the damn thing, so I certainly don't know the intimate details of the construction materials used.
I also respectfully request that you don't tell me that I gave you information previously that I couldn't have given you because I never knew that information in the first place.