[Binx]

A way could be with MySQL. The owner, for example, makes a key in a table and the item to give(whether it being a vehicle or a weapon) and when you type in the "name" of the key, it'll grab the data from the database and process it, giving you the item.
For example, the table could be:
ID, Name(being the key), vehicle(Yes or no or being the ID of a vehicle), Weapon(yes or no or being the ID of weapon)

This is personally the way I'd do it.