couldnt u just set the value on the heros u want to be sold at the tavern (Stats - gold cost, Stats - lumber cost), go to the tavern, go to techtree - units sold and add the heros, and then go to abilities - normal and add sell units, invulerable (neutral), and select unit. then u should beable to accually sell the units for gold / lumber without needing triggers, if thats what u meant