How to promote site services by region and get rid of duplicate pages?

Question

Search Engine Optimization

Good afternoon!
We really need advice on how to properly promote the site's services by region without duplicate pages.
Site services are provided in 4 regions. The content of each of the regions is located in separate directories on the main domain [main region] and looks like (main region.ru/other region). Content, namely the main page, services, etc. are identical in all regions, and therefore there is a problem with duplicates.
I re-read articles on the Internet, as well as similar questions published here earlier - almost everywhere they write that regions need to be moved to separate subdomains, but even if the number of regions does not exceed 7 and the materials are similar in regions, then it is better to stop at subdirectories.
Can you tell me how to get rid of duplicates? Can I somehow set up robots.txt or some kind of redirects?
Now the site services already have positions in different regions, but they are not desirable enough. How then to promote duplicate pages if they are closed from indexing?

Answer 1

Subdomains are preferable because each of them can be added to Yandex webmaster and assigned the desired region.
If I were you, I would not bother with the problems of "doubles", tk. page duplicates are considered within a specific domain. If you make subdomains, the pages will not be considered duplicates, they simply will not have unique content, but if you are going to promote them in different regions, then there is nothing criminal in this.

Answer 2

So leave the main page for all regions - the main region.ru, and then divide it where it differs by region.

Answer 3

If you divide the site into regions, then do it right. I have an online store of 196 cities on my website. And you can get to each directory at /city/directory_address, so that search engines do not consider duplicates, you need to add the name of the region in which we are now to the title and description. That is, if we switched to the main domain, then nothing is added, if the region is specified, we add it to the title, that is, Goods for cars in Moscow, Goods for cars in Vladivostok, etc.