No doubt Google announcement has turned an uptake of HTTPS implementation by marketers. From the SEO point of view the green bar SSL Certificates creates trust to the users which further helps in boosting conversion rates. Overall your web-page visibility will improve. The SSL certificate enables security for online credentials and data transfer. With the padlock and HTTPS it makes secure connections from server to browser. But, as not all the provider offers the same type of certificate, hence, choosing the right type of SSL certificate can be bit complicated. However, there are three types of certificates:
Domain Validated certificates (DV), Organization Validated certificate (OV) and Extended Validation certificates (EV).
From the above it come with the level of protections, LOW, MEDIUM, HIGH. Try to identify your needs with the Domain or Sub-Domain and then choose the type of protection accordingly.