can_make_expensive_purchase_trigger

can_make_expensive_purchase_trigger = {
	OR = {
		# Players can make their own decisions.
		is_ai = no
		# Some people are just really bad with money.
		has_trait = profligate
		## If a purchase is unwise but would be magnanimous, save this scope first to flag it as valid in the event.
		### If you're in a chain, don't forget to clear the scope up afterwards with clear_saved_scope, otherwise it might affect other usages of the trigger further down the chain.
		AND = {
			has_trait = improvident
			exists = scope:generous_purchase
		}
		# And if you've got the cash to spare, who cares?
		short_term_gold >= $PRICE$
	}
}

As written in game/common/scripted_triggers/00_economic_triggers.txt.