In terms of what many vendors call unlimited service, Web Hosting Pad's terms of service indicate that its definition of unlimited is what it calls "incremental." Basically, as you need more capability, it wants to discuss that with you, both to help you get the most out of its services, and to make sure you're using its systems without abusing them.
No. An SSL can only be installed on a single "hostname", which is one variation of one domain name. SSLs do not cover multiple domains, or multiple subdomains. For example, you can install an SSL on store.yoursite.com, but then it won't cover yoursite.com, and vice-versa. It only encrypts the hostname it's installed on. (A Wildcard SSL covers every hostname of a single domain.)
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