Hero Selection Trigger Problems

Having problems with my Hero Selection.
It goes like this:

1. Map starts in cinematic mode and zooms into this group of Acolytes.
5 small Acolytes and 1 "boss" Acolyte. The 5 small ones represent each player playing and the boss Acolyte is like the store where u buy(select) your hero.

2. Player control enabled, the player can now choose a hero to be summoned by the boss Acolyte. When a player select a hero from the shoplist, cinematic mode is turned on again and u see the boss(the shop) Acolyte do a summoning move and the small Acolyte representing the player dies. Now the Camera moves to another place on the map and u see after a few seconds that the chosen hero is summoned.

3. Camera returns to normal game view and player control enabled. The hero is selected.

All this i have managed to do, but i dont know how to only make 1 player allowed to summon a hero at once. Thats what this post is about.

I tried to use the turn on/turn off triggers but that wont work correctly since the boss acolyte is a shop and even if the summoning trigger is not active the chosen hero will popup next to the shop...and that will ruin my design.

I hope u guys understand some of what I've tried to explain and can help me. If not, I could try to explain better and maybe even attach a version of my map.

Try to use dummy items in the shop and only fire the summon trigger if the player doesn't have a unit yet. If else just give a message that the player already has a hero.

Thx for quick reply, but the problem is that the summom trigger cant run for two players at the same time...and if a player buys a hero at the same time someone else are running the summon trigger it will buy the hero, but not summon it correctly just appear next to the summoner as normal.

BTW, is it some kinda "auto-que" system that only allows one player to run a certain trigger at a time? Are there any workarounds?

You can make it so, that if one player selects the shop/acolyte, he will now controll that unit, making others unable to select it and they must wait until the unit is deselected or the player bought a unit.