the landing-page would need to include a
secure e-commerce method to purchase
the item.
google has rather strict rules for
submitting marketplace items --
such as a shared common site.
for example, the marketplace is
responsible for all feeds, each
merchant (marketplace-seller)
must be given a sub-account
under the marketplace-account,
prices must be fixed, duplicate
listings from multiple marketplaces
are generally not allowed, items
may not be submitted on behalf
of any merchant with existing active
listings in product-search, a proper
image must be submitted, proper
global-trade data or an exemption
is required, etc., -- in addition to
google's general rules and policies
for feeds, items, and websites.
if only one submitted item violates
google policies the sub-account and
marketplace can be disapproved.
generally, you submit the marketplace items
on behalf of sellers and use the same upload
techniques available to individuals -- feed file,
manual-upload, scheduled-fetch, ftp, or api --
within the context of your multi-client account.
details about getting started should be here:
http://support.google.com/merchants/bin/answer.py?answer=160489for more information on marketplace policies --
http://support.google.com/merchants/bin/answer.py?hl=en&answer=160607