What are SEO recommendations for regional subdomains of an online store?

Question

Search Engine Optimization

Good day to all!
The bottom line is, there is an online store that plans to move to 17 different regions of Russia. Since the priority search engine is Yandex, there is no way without creating a subdomain for each individual region.
In this regard, the question is, what are the nuances in terms of SEO for regional subdomains? What should be the SEO text on subdomains, can the content duplicate the one on the main domain. What addresses and other contact details do I need to provide? What is the best way to relink (link) subdomains with the main domains and do they need to be linked at all? If someone faced such a task and made a detailed TOR on this matter, please help! Thank you all in advance!

Answer 1

in short, you need to understand why this or that on the site - the leader is made
about subdomains, the rule is the same as in general: different unique content if it depends on different regions : if your St. regional content, if not - I will zaipetsya walk through subdomains with all the consequences

Answer 2

The most important thing is to have an office in the region or a representative office, because I and G are not limited to calls, but come to the place and check. Sometimes they call the shopping center (if an office is indicated in it) and ask if there is a contract with such and such a company for rent.