Enum PlotPlacementResult
Why a structure could not be placed on a plot.
public enum PlotPlacementResultFields
The structure may be placed.
The plot is not in building mode.
The character does not own the plot.
The structure would intersect something already built here.
Some part of the structure would fall outside the plot.
The plot could not be identified, or has no database row yet.
The structure template could not be identified.
Remarks
Distinct reasons rather than a bool, because the server refuses placements the client already thought were fine — clock skew, a plot sold out from under someone, a template that was removed — and "no" with nothing after it is indistinguishable from the request having been dropped.