Barcelona

You must take your two Citizens and place them (in any order) on a single street crossing that currently has no Citizens; placing two is the mandatory first step of your turn. (Rulebook, p.6)

No — after placing your Citizens you may perform any or all of the street actions available at that crossing in any order, but each action may be performed at most once. (Rulebook, p.6)

Players placing Citizens on a space covered by an Intersection do not have to pay that space’s depicted cost, but when you build an Intersection you must pay the Intersection’s printed cost (and any extra cost on the chosen space) even if Citizens cover it. (Rulebook, p.8)

After the first placement, you must move your Tram one or two street spaces away; movements through your own Street tiles are “free” and do not count against the two-space limit, though you cannot end on a space with another Tram or stay in place. (Rulebook, p.11)

Constructing a Building at the end of your actions is mandatory whenever you can; if you have no Building markers left you still construct the building (you simply don’t place a marker) and still gain VP and effects as normal. (Rulebook, p.12)

A Cerdà Scoring is triggered at the end of a player’s turn if any Citizen track section is filled to or beyond a marked Cerdà Scoring space, then all players score that section’s face-up Cerdà tile; after the scoring you discard all Modernisme tiles on display and reveal four new ones. (Rulebook, pp.14–15)