improvements cost

[omnibus]

I'd like to know, if cost of city improvements is charged at:
1) civilization level - all cost is summed for all cities and deducted from total civilization gold or
2) city level or
3) combination of both

In case of 2) is correct I wonder what happens if a particuar city doesn't have enough gold to pay all its improvements.

Thanks

[J Bytheway]

Improvements are paid for after all other modifications to gold, i.e. at the civ level. If you don't have enough gold your wages will be lowered, and if you still don't have enough then cities will sell their improvements. You should really be able to switch that around, but never mind.