SEO articles for the online shop of bathrooms

Don't Look is a brand that sells design bathroom. My partners are engaged in SEO optimization and promotion of this online store across Ukraine, and I do blogging. SEO copywriting gives good results, the main thing is to blog and other content on the site regularly. Articles have keys, they are included according to the rules, so search engines do not consider such content a spam and willingly show this site above the similar ones. They usually order a package of services for SEO movement, this service is paid for a month in advance. On average, the cost of all SEO works is 300-400$. The cost depends on the site and the niche. Each month, at least 10 such articles are required to promote. They are useful for both searchers and visitors. 10 SEO articles cost me from $100, depending on the complexity of the topic.