This extension allows a superadmin to create a transaction for a customer by assigning a member id in the checkout form.
Add an input called "checkout_as_customer_id" with the member id you want to assign the purchase to. Set the checkout_as_customer_id parameter to "yes" as well
{exp:cartthrob:checkout_form return="" checkout_as_customer_id="yes" }
{gateway_fields}
<input type="submit" value="Checkout" />
<input type="hidden" value="123" name="checkout_as_customer_id" />
{/exp:cartthrob:checkout_form}
This is a standard EE extension which is installed & configured like other extensions: Installation: move file to system > expressionengine > third_party Follow additional installation instructions here: http://expressionengine.com/user_guide/cp/add-ons/extension_manager.html
This add-on is provided as-is at no cost with no warranty expressed or implied. Support is not included.