Sandbox mode?

[Kosov98]

I would like a sandbox mode, just so I can relax and build a base. There used to be a mod out there that made the whole game sandbox mode but has since been abandoned. Maybe just a checkbox on new game startup?

[DTD_Hiro]

I would like to second this, but with an addition.

When in sandbox mode, the game calculates and displays the cost, in resources, of whatever you have placed, broken down by type if possible.
So if I go into sandbox mode, drop a bunch of walls some buildings, etc, a list appears showing me how much everything is going to cost. (30 building materials, 10 copper, 50 metal plates, etc.)