Does it matter from where I will buy a domain that I want to resell? Regarding the possibility of changing the domain owner and etc? Do all registrars offer the possibility of transferring the domain to a new owner?
It doesn't matter where you buy your domain, you still have the option to transfer the domain to the new owner.
It absolutely matters. Transfer is much smoother if the new owner has an account with that registrar. As a buyer, I have no problem opening an account with, say, namecheap or godaddy but I might be wary if it's hackers4u.ru Go with a registrar that has a good reputation and is reasonably well known.
Yes my friend, it absolutely matters. Your domain and domain name provider needs to be ICANN accredited and also must follow all the stringent rules as laid down by ICANN. I chose BigRock for the same reason and because their pricing is affordable for my clients. Also, these factors make domain name transfer decisions easier and processes less complicated.