I just wanted to correct this misconception:
Just to make things clear, installing an SSL certificate is not possible because there is no dedicated IP address for web hosting.
While this may be what your hosting provider has told you, it is not a fundamental property of SSL/TLS and in most hosting environments is not true.
The misconception stems from the fact that the
Host: header of an HTTP request is encrypted within the SSL stream and hence for many years the only way to distinguish which SSL certificate should be used on a server that hosts multiple websites was to have one IP address per SSL certificate.
To address this problem, SNI was created as an extension to SSL/TLS. If both the client and the server support SNI, any number of SSL certificates can be served from a single IP address. SNI was first practical in 2008 and is quite widely supported these days but you should check the clients you actually see on your website against the list of supporting clients in the Wikipedia article.
If a request is made where either the server or the client do not support SNI, the behaviour of Apache is to choose the first SSL certificate in its config and use it. This will cause a warning in the browser but if the user chooses to ignore the warning an encrypted connection will still be made, albeit negotiated with the wrong certificate.
For the sake of accuracy/completeness, in the above case eavesdropping would be possible by someone who had access to the private key of the default SSL cert in your Apache configuration but since they would require root privileges on the same box where your cert is stored I don't see this as a significant threat. Teaching your users to ignore SSL host mismatch warnings is not a good practice anyway and suggesting they upgrade to a more modern browser/OS is much better from a security perspective.