This is a new technique in Vectorworks 2017. You can use a level to control the insertion point of a symbol. In this example I have a symbol for a power outlet with a 3D component. If you create a level for this symbol, you can set the height of the symbol using the level. When you need to change the elevation of all the power outlet in that story, change the level elevation. All the power sockets on that story will update.
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