Please i have question :
what kind of traffic you used the sellers : email, display, social media...?
To deliver traffic, the solo ad seller emails ads to his email subscribers.
You can check this link to understand how to buy: https://udimi.com/help/buyer/how-to-buy
Check this as well: https://udimi.com/help/buyer/how-udimi-click-filter-works
I understand why you would ask such a question.
Allow me to give you an insight to my traffic:
I use Email traffic only, the leads are prequalified with a web form ie:This data consists of people who went to a biz opp website and filled out a form inquiring about a work from home opportunity.
They are then cleaned and all bad emails are removed to make sure only real quality visitors are sent to offers which results in greater optin rates and higher sales count.