It is possible to buil several subdomains (same domain) hosted in different companies ? .
I've read some posts out there, but nothing of value about this matter
Yes, not that hard at all. One of the hosts will have to have your DNS settings. Then on whatever host you have your DNS setup, you can add your subdomains and point them to any host, server, etc you want. Look into Authoritative DNS, DNS C Records.
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