You can — but in moderation. Your hosting service is NOT an online hard drive. We have found customers uploading all their computer files as if their hosting were a backup of their own machine. This type of use is not accepted on unlimited plans.
The ownCloud usage limit on your unlimited hosting plan is 500 MB — enough space to store that small group of files essential for running your business (photos from your brother's wedding are excluded).
If you need an ownCloud or similar service on your hosting that goes beyond 500 MB, we can of course offer that by billing you for the extra space needed. To arrange this, contact our technical team at ayuda@Bacan.com.