Board Thread:Questions and Answers/@comment-24.168.250.116-20131202180652/@comment-5596770-20131203180942

2nd and 3rd Station use the same inventory as the primary station. You may place any building you could in your primary station into your 2nd and 3rd station.

Note that some special buildings (such as Stock Exchange) do not provide their bonus if placed in 2nd or 3rd station.