Hyper-V is a type of Virtualizatio used to create Virtual Servers on Dedicated Server.
Yes, we only provide DDOS protected servers.
No, VPS are not refundable.
You are responsible for your backups and web content. It is recommended that you keep copies of your content safe and make your own backups. You can take a backup using hosted application backup solution or use a remote backup solution.
You can upgrade the VPS, but downgrade is not possible with any VPS plans.