1. It was so inconsistently applied on building VS its requirement, that it was faster to remove it for a timehey, anyone knows when I can construct buildings like town hall or jeweller in cities below size 3? I'm almost sure that some days ago there was min size 3 requirement, but maybe remembering wrongfully. today I noticed I could construct these in sizes 1-2
edit: question 2, how do you get city celebrating (0 maintenance cost)? I feel like it's random
2. It happens if happiness is higher than unhappiness, so always. Then it has random chance of triggering it.