if no gloabl-trade values exist
do not submit any global-trade
values (gtin, brand, or mpn).

if no global-trade values exist simply
contact google for an exemption.

if global-trade values do exist, age and condition do not matter.

google does not want global-trade data that does not exist.

variants are only required if you
offer the item in variants -- if there
are no variants simply do not submit
item_group_id and submit a single item.

google does not want variants if variants do not exist.

classification is by physical type of item not age or condition.
e.g. for google_product_category simply use:
Apparel & Accessories > Clothing > Outerwear > Coats
for product_type you may use any value you wish.

for non-variant u.s. clothing google simply requires --
color, size, gender, age_group
apart from the standard required attributes such as price.

for non-clothing apparel items such as handbags size is not required.

the price submitted to google,
the price displayed on the webpage
and the default add-to-cart price
must all match exactly at all times.