Code:
#==============================================================================
# ** Store Goods Wipe
#------------------------------------------------------------------------------
#    by DerVVulfman
#    version 1.0
#    01/17/2018 (MM/DD/YYYY)
#    RPGMaker XP / RGSS
#------------------------------------------------------------------------------
#
#  INTRODUCTION:
#
#  This script is just something I cobbled together to erase the contents
#  of a store's inventory before it is called. This is a useful script if
#  the end-user is adding inventory itsms of their own and wishes to have
#  only their goods rendered.
#
#  Please note placement.  This 'SHOULD' be above other scripts that may
#  affect a store's inventory.  But that will depend upon the script.#
#
#  To install, paste the script between Scene_Debug and Main.
#
#  To use, make a Script Call as follows :  $game_temp.store_wipe = true
#
#  That's really it.
#
#==============================================================================
#==============================================================================
# ** Game_Temp
#------------------------------------------------------------------------------
#  This class handles temporary data that is not included with save data.
#  Refer to "$game_temp" for the instance of this class.
#==============================================================================
class Game_Temp
  #--------------------------------------------------------------------------
  # * Public Instance Variables
  #--------------------------------------------------------------------------
  attr_accessor :store_wipe               # Force store inventory erasal
  #--------------------------------------------------------------------------
  # * Alias Listings
  #--------------------------------------------------------------------------
  alias game_temp_store_erase_initialize initialize
  #--------------------------------------------------------------------------
  # * Object Initialization
  #--------------------------------------------------------------------------
  def initialize
    # Perform the original call
    game_temp_store_erase_initialize
    # Set store erasal to false by default
    @store_wipe = false
  end
end
#==============================================================================
# ** Interpreter
#------------------------------------------------------------------------------
#  This interpreter runs event commands. This class is used within the
#  Game_System class and the Game_Event class.
#==============================================================================
class Interpreter  
  #--------------------------------------------------------------------------
  # * Alias Listings
  #--------------------------------------------------------------------------
  alias interpreter_store_erase_command_302 command_302
  #--------------------------------------------------------------------------
  # * Shop Processing
  #--------------------------------------------------------------------------
  def command_302
    # Obtain the effective return flag
    effective = interpreter_store_erase_command_302
    # Erase store contents if flagged & reset flag
    if $game_temp.store_wipe == true
      $game_temp.shop_goods = []
      $game_temp.store_wipe = false
    end
    # Return effective flag
    return effective
  end
end