Reddit mentions of Keen Foamboard A3 x 5mm White (pack of 10)

Okay, to kick things off, here's a handful of things I cannot work without.

• Plasticard - Thick plasticard is quite hard and tough, while thinner (1mm or less) is quite flexible. I primarily use it for terrain bases. It comes in various thicknesses and has many other uses.
  
  
• Foamcore - Foam/sponge like material sandwiched between 2 sheets of card. This is my stock material for buildings and ruins, buildings, bunkers, aegis defence lines, etc. Easy to work with, great results. One thing worth mentioning is that if you're gluing exposed foam, you should give it a coat of paint first, as superglue/polystyrene cement will melt it.
  
  
• Sand - I don't think a link is needed for this! I use both fine grain sandpit playing sand as well as coarse building sand (the latter usually contains small stones that are also useful). If money is tight and you're buying from a home depot, poking a few holes in the bags can get them reduced (just don't get caught!!). I paid £1.20 for 2 massive bags (c15kg's each).
  
  
• Glue - Lots and lots of glues. Superglue, Epoxy Resin, Poly.Cement, PVA, Gorilla Glue, Hot Glue Gun. You can never have enough glue.
  
  
• Wire - Various thicknesses. Usually copper, as it is sturdy but easily manipulated.
  
  
• Gause - Really cool stuff. Great for fences and windows, etc.
  
  
• Cocktail Sticks - Useful for using as fence posts, rebar's, etc.
  
  Then I hoard everything else. Bottles, cans, tins, chain, spare screws, bolts, springs, etc. Unused parts from sprues. You can search on ebay for "40k bits" and buy boxes of unused spare parts for relatively cheap which can really add some detail to your models and terrain.
  
  And that's my tuppence!