You can ask any professional website promoter, and get a single answer, that every website is unique, so, the cost of its promotion depends on various factors. And yet, how can you estimate the cost of your website promotion?
As you cannot buy TOP ranks in the listings of such search engines as Yandex, Google, etc., so you should use SEO to get it. But, good promotion of any business website can cost a lot, because, many companies in every sector compete for the high ranks in search engines.
Рассмотрим из чего формируется стоимость продвижения сайта.