question

>> Does the item id have to be in a store to purchase?

No, it doesn’t. Players can purchase the item in the catalog directly. But if you don’t set the price for the item in the catalog (leave the price as empty), players will be unable to purchase it from catalog.

>> I am assuming a player could look at this or just make a request and then purchase an item that is listed in this catalog that is not listed in a store?

Yes, technically, the players can buy any item from catalog when this item doesn’t be listed in the store. As the first answer said, to prevent it, you can leave the items’ catalog prices as empty.

>> The purchase request has an optional store parameter to use for pricing. Is it not possible for a player to recreate this request with a item and leave the field empty to use the catalog price while the price is different in the store pricing? Possibly getting the item cheaper?

Yes, you can leave the field – “StoreId” as empty, if so, the player will purchase items from catalog. In this case, players can purchase this item as its price set in the catalog. To prevent players from purchasing the item using a cheaper price, you can set the price of the catalog as a higher price or don’t set it. Besides, you can also set a Rule to trigger a CloudScript function execution using the event “player_vc_item_purchased” to validate whether this player purchased an item from catalog or store.