SSL is pretty simple than it seems to be, you have 2 options: Free SSL or Commercial (Paid) SSL. Free SSL 1. Let's Encrypt 2. CloudFlare SSL (there are a number of options below) Flexible SSL means there is no secure connection between CloudFlare and your site, but the connection between the visitor and CloudFlare is secure Full SSl means that both connections are secure, but the connection between CloudFlare and the website does not check if the website has a trusted certificate: self signed will do as well. Full Strict SSL: most secure. Everything is secure, and the website needs it’s own trusted SSL certificate. Commercial SSL Certificates bought from distributors / hosting providers / etc. In this case you have to pay for the SSL and then configure it on your hosting account. See info regarding offers above.
Yes, free options are good for startups and bloggers but I am afraid you have to renew it after some time because there is no long validity. Extended validation and multi-domain are not available as free. I would suggest getting an SSL from authentic SSL partners and resellers who provide at best price compared to CAs.
There are cheap SSL certificates and FREE ones as well. From Let's Encrypt to Comodo certificates. Soon I'll post a guide on how to get a FREE Comodo certificate.