
The idea is that a "tool symbol" would appear at the default teleport point of the sandbox on the map. In the example above, you can only teleport to the ABC Sandbox atthe entry. I used a spanner & hammer symbol, but any suitable icone could be used.
That way, if you have the "urge to build", or need a sandbox in which to rez and open a purchase, you can easily see where the nearest one is, and go there.