Alternatives
Yes, you can keep your documents on Dropbox, iCloud, Google drive, OneDrive (Microsoft), or even AWS (Amazon Web Services) cloud storage. If you have a hosting service they may allow you space to store your files. However, the downside is for most of these services the support staff and perhaps others in the support organization for that service, will have access to your private documents and photos.
Ideally your files should be encyrpted so the service provider cannot view the contents of your files. This suggests you would encrypt your files before uploading them to the file sharing service, or use one of the options listed in this article.. Several encrypted cloud file services where you control the encryption keys, are described in these sources:.
FidSafe is a free service offered by a group that appears to be affiliated with Fidelity (investments). They have a comprehensive list of documents that are candidates for your consideration as worthy of having a good copy. In any cloud storage service, it only seems a good idea to encrypt any file before you upload it to such a service. This is not a ding against Fidelity, it is a stark recognition that even organizations with very good security are targets of widespread attacks and can be compromised. The simple fact that this is advertised by Fidelity, makes it more of a target because everyone knows where it is. My-Stash, however, is designed "not to be found": if attackers can't find your site, it's harder for them to attack and compromise it.