Basically this...
https://digitalocean.uservoice.com/forums/136585-digitalocean/suggestions/3127077-extra-diskspace
... but with HDD instead of SDD. For my use cases, SDD is overkill. So is it's price. At HDD prices (https://www.time4vps.eu/storage-servers/) you can get 2TB at 12.5$/mo. That volume costs 205$ with the DigitalOcean SDD storage offering...