Yes, you can host up to 5 different websites on the same hosting plan.
What you should watch out for:
- The size of the websites.
If a site is big, then it is likely that it consumes quite a big part of the available iNodes of the package, that are 100000. Every file of folder or email is an iNode, so a typical WordPress site has usually 5000 to 10000 iNodes. Therefore, if you have 5 small websites you will be able to host them to the same hosting plan.
- Security issues
What you have to keep in mind is that all the websites that are hosted by the same hosting plan, are in fast located in adjacent folders within the same package. So, in case of a website violation, there is a possibility that another co-hosted one might be affected as well.
The above fact does not apply to cases when every website has its own cPanel account, since each one account has its own user in the operating system and is protected by the operating system itself.
Thus, if you are planning to host open source applications, you need to be constantly aware of the available updates, as these applications are usually targeted for malicious attacks, if they are not updated. In case you have custom applications or static html pages, the risk is significantly lower if you are planning to host all your sites by one hosting package.
- Adequacy of resources
The Standard Power hosting plan has specific system resources (CPU, RAM, I/O, Iops), that are used from the sites that are being hosted. If a site has more requirements in resources then it is likely that it consumes a significant portion of the given resources or even all of them and thus makes the other pages delay. If for example, a site has a mechanism that is not functional and produces a lot of CPU consumption, then it is possible that all the sites of the hosting plan will be slow as the CPU usage will have been drained.
The above case is something that doesn't occur when there are separate cPanel accounts since the site has its own resources and thus, in case of a malfunction, it cannot affect any other site. None of the websites can exceed the resources given by the hosting plan, so it cannot exhaust the server's resources, but only its individual ones that are a subset of the total resources of the server.