Mod v0.0.1
Change landfill stone cost is done in game interface:
1.Settings > Mod settings > Startup
Special thanks to Pi-C for improve source code
Mod v0.0.0
Change landfill stone cost is done in mod files:
1.Open folder: "LandfillNEWcost"
2.Select file: "data.lua"
3.Open it: Right mouse click > Open with a text editor
4.Find line: {"stone", 4}
5.Change value "4" to your own
6.Save