How to correctly build and organize a grid of sites?

Question

Search Engine Optimization

hello,
there is a service, the client plans to develop it first in his region, then throughout the country.
site is not yet available. Templates will be almost the same depending on the city. In this case, we are talking about a one-pager, but it is possible to expand into a full-fledged site
, in connection with which the questions are:
- how to make 30-50-100 sites in terms of further promotion? one of the options: make a "main site", and make a subdomain for each city. what are the other options?
- how to effectively manage all this, for example in WP?
- how to properly organize a backend for a huge number of subdomains and what should be taken into account in general? - 95% identical content will not cause a ban? what is the best practice in terms of SEO?
Is it worth it to do everything on 1 hosting?
— what best practices do you know for building site grids?
I will be glad for useful links, videos, proven and relevant articles and your wonderful recommendations,
paseeba :3

Answer 1

- how to make 30-50-100 sites in terms of further promotion? one of the options: make a "main site", and make a subdomain for each city. what are the other options?
If the site is commercial and "white", and not doorways, then do exactly as written, that is, one main site and subdomains for different cities. You can make a division within the folders or change the content depending on the selected city on the main domain, but in practice it is the subdomains that work best.
There are plugins that allow you to do a good division into subdomains in many CMS.
Again, you need a good plugin and the advice of a competent SEO specialist.
If the project is "white" then yes, you can do everything on one hosting.
Will not.
You do not have a grid, you have a regional division into subdomains. The network is something else.