Conversion Rate Optimization (CRO) services employ various pricing models to cater to a diverse set of clientele. Common structures include hourly rates, where clients are billed for time spent on their projects. Project-based pricing involves a fixed fee for the entire project, providing cost certainty alongside predefined scopes. Some CRO agencies also retainer agreements that come with a monthly fee for continuous optimization.  Each model comes with its own set of advantages and disadvantages. Selecting the appropriate model will depend on the project's complexity, time period, and budget.