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This link would typically be placed on your website wherever you showcase your wholesale program. It would have some verbiage to encourage the prospective customer to "Click Here to Signup". The following is an example of UltraCart's Wholesale Signup screen (application) with minimal screen branding: 
Wholesale Login Link
On a different screen or possibly on the very same wholesale screen, merchants will place their Login link. This allows existing Wholesale Customer to login and be taken to the merchant's wholesale screen that displays all the Wholesale items, prices for Wholesale Orders. 
Wholesale Logout Link
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