This engagement model is best fitted for medium to large scale businesses as they already established their basic system, processes and policies in place which runs their day to day operations.
When your business has a clear vision for the future with enough potential to operate for long term, a retainership model can prove to be a right choice for entrepreneurs. Retainership model, besides being cost-efficient, will allow you to have a dedicated agency which will work by putting their legs in your shoes.
This model focuses more on long term partnership between the business and agency by entering into a longer-term agreement where the focus is fully on continuity and keeps evolving. In scenarios where your dedicated team fulfils your broad range of services and deliverables, the way to go is with a retainer model.