Where is the cheapest place to buy ssl certificates and a couple more questions about them?

Question

Encryption

Hello. Forgive my incompetence. Actually the first question is in the title. Where can you buy and cheap?
Do I understand correctly that a self-generated certificate via openssl would not be the best solution because browsers would ask about trusting the origin? Can the same certificate be used for multiple virtual hosts on the same server?

Answer 1

Letsencrypt is not yet in beta for everyone.
Where to buy correctly listed. I'll add firstssl.ru - comparable in price, Russian bills, Russian support.