How big is the complexity of the task of choosing the optimal advertising or choosing performers for effective website promotion in search engines?

Question

Search Engine Optimization

There is a task to attract more new customers, but it must be solved in such a way that the cost of resources for advertising, SEO optimization of the site and other things from this area fight back, and not reduce profits. How difficult is this task, what is necessary for its effective solution? The organization is engaged in the installation of fire protection systems.

Let me give you a negative example: the SEOs have been shamanizing something with the site for a year and in the end their activity did not bring any effect - this conclusion was made based on the fact that the flow of customers from the site they were engaged in remained close to zero, and customers were attracted in other ways . How not to step on such a rake?

Answer 1

Dynamic and fair percentage of sales : 100/(2+N)
N is the number of sales in the last 30 days.
Warn immediately that payment for one-time paid third-party services for promotion (purchase of banners, publications, etc.) is 50/50 (half) with those who promote and by prior agreement.
PS:

Let me give you a negative example: the SEOs have been shamanizing something with the site for a year and their activity did not bring any effect in the end.

this is almost a 100% situation, so I thought for a long time before solving a similar problem for myself once and for all.

Answer 2

Enough good margin to cover costs