I do not believe that Contabo sets up a bitcoin node for you though - I think you have to do that yourself, and that they only supply suitable hardware for it.
Why don't you believe? It's already shown that an image is already prepared for launch. I think it would be setup already, probably have to add something before it starts, maybe the blockchain is downloaded or something once they have launched your VPS.
It probs includes the bitcoin core daemon and client themselves, but I have never seen a VPS host automatically run software on your box when you boot it. You would have to do that yourself. Ergo, that means you have you manually start Bitcoind so sync the node, which means that the nodes are not fully synced (besides do you really think the images are kept up to date with the current blocks and chainstate? That would be expensive for them to store that AND keep backups/snapshots of all the images daily.)