You could check out Amazon AWS, probably the cheapest cloud option, as you pay for the usage. There’s different availability zones during outages(unless its a DNS outage) which can be much worse. Then you can simply mount the AWS points as shared folders in linux/windows. Make sure you have multiple admin backups because if you lose all the admin hash passwords, not even amazon can help you.
You can also simply share a local machine if you have fiber, but if your ISP goes down, everything goes down.