Hold Item For Specific Customer Only

I have a very good customer that needs me to hold an item from the store to ensure he is the one to order it. Is there a way to make this item available only to that customer?

You could customize the functions_general.php in the function zen_get_buy_now_button and add the code in RED:

    switch (true) {
[B]// limit products_id 12 to customers_id 123
    case ($product_id == '12' && $_SESSION['customer_id'] != 123):
      $return_button = '<a href="' . zen_href_link(FILENAME_CONTACT_US) . '">' . 'LIMITED PRODUCT' . '</a>';
      break;
[/B]// cannot be added to the cart
    case (zen_get_products_allow_add_to_cart($product_id) == 'N'):
      return $additional_link;
      break;

which would only allow products_id 12 to be purchased by customers_id 123 ...