Reddit mentions of EnderToys Brick Walls, Terrain Scenery for Tabletop 28mm Miniatures Wargame, 3D Printed and Paintable

I found some cheap terrain on Amazon that happens to be well sized for Guild Ball and was pretty easy to paint. Take a look:

• Walls (2 low, 2 high)
  
  
• Barrels and crates (5 of each)
  
  
• Chests (4 I think - I didn't get these)
  
  
• Broken columns (4 I think - I didn't get these, either)
  
  
• Tree stumps (3)
  
  Of the ones I got, obstacles can be made with groups of the barrels and crates (a few crates, a few barrels, or a combination of both), the low walls, and the tree stumps. The high walls make nice barriers. While I didn't get them, I imagine the chests and columns could be added to either obstacles or barriers, as well.
  
  Here's a picture of all the terrain I made after assembly and priming. Here's a picture of one of them after being painted fully.. Unfortunately, I don't have a group shot after painting.

https://www.amazon.com/Paintable-Brick-Walls-Printed-Buildings/dp/B00TO07GMM

They paint up great after priming. Considering buying another set since they ended up being the most used pieces during our last game session.

You can use anything as terrain as long as you define it. You can use a Pringles can and say it's LOS blocking but you can't go on top of it because <insert reason> as long as your opponent agrees.

If you're looking for low cost terrain I have used stuff from this site such as the abandoned buildings. You print them on plasticard and you can build various heights with these. The abandoned building prints out with a choice of 1, 2 or 3 stories and you can print as many or as little as you like. They have access points (Doors) and balconies that you can perch a model or two on to shoot off of and give some cover.

You don't have to break the bank for terrain. What you're looking for is:

• Line of Sight blocking terrain
  
• terrain you can hide behind and use as cover (like ruins or a barricade walll)
  
• terrain that is used as difficult, dangerous or impassible terrain (Craters, a lake or a pool of lava)
  
  If you have those three things, in any number on the play field, it'll be a much more fun game that gives you the ability to maneuver and get into a good firing position.
  
  I also purchased these which were very cheap and work very well for something to hide behind. Because they can be made into a "Box" you can turn them into Ruins for the 4+ cover save as long as your opponent agrees.