Basis DSP buys inventory solely on a cost-per-thousand impressions (CPM) basis. There are many factors that play into the price of each impression, but ultimately prices are dictated by supply and demand.
It is, however, possible to optimize your campaign to a specific CPC (cost-per-click) or CPA (cost-per-acquisition) goal since we report on these metrics in real-time, on a campaign, site, and placement level. Basis DSP's built-in Optimization feature allows you to set a CPC or CPA goal that placements in your campaign must meet. See Optimization for more information.