Which SSL certificate to choose for a web server?

Question

Web servers

Good afternoon!
It is necessary to choose an inexpensive certificate for the main domain and several sub-domains of the web server, and:
1. The green line is not necessary, but browsers (ie, firefox, chrome) should not "curse" on the site when entering
2. ClickOnce should accept it as valid and check the data on the server.
3. Preferably one certificate for the entire domain (although if 3 is cheaper than a wild card, then it's not very important).
The main criterion is the price and it is desirable that the company to which the certificate will be granted is located on the territory of the Russian Federation.

Answer 1

3 certificates usually come out cheaper than 1 WildCard.
Look here: https://www.isplicense.ru/services/ssl-sert/rapidssl/
A discount is possible for 3 certificates. There will be no errors with correct installation (and here it is free) in any browser - checked

Answer 2

I join Flantru. If we are not talking about protecting under 100 subdomains at once, then I would advise you to take a simple certificate with domain verification, for example Comodo PositiveSSL
Options with prices:
masterhost - from 2800 rubles/g
Sslcertificates - from 900 rubles

Answer 3

SSL has been discredited a little more than completely, so now is not the best time to attach a certificate to the site.
Any cheap/free certificate will be yelled at by browsers in huge red letters "SCAM HERE, GET OUT OF HERE". I don't think your clients will like it.

Answer 4

StartSSL.com - gives free certificates, no different from paid ones. The main thing is that the project is not commercial (if there are prices on the pages, etc., they will not give a certificate)
Take a certificate for each subdomain. wildcard will not be given for free, of course.