Common house rules?

[Montana_Prussian]

There are no house rules that I know of, you need to negotiate before every battle what you want to use.

For example, I do shell on turn 0 if I think it's wise, no one has taken offense so far.

About 10% arty, some count every piece that is able to fire indirect, some allow 10% plus company attached mortars, some include airforces, you need to agree how you count it.

I never count direct fire only weapons in the arty. Shelling on turn 0 is fine by me in Assault or Advance.