I have a powerfull and, hence, expensive VPS which I can use to bootstrap Daedalus and my personal laptop which then will use to run the wallet after it’s been bootstraped.
Therefore, can Daedalus be used this way: boostraped on one machine and then used on other?
If so, how would I move it, and its data, over to my local laptop - what directories would I have to copy?
Will I have to move over all the blockchain, 70Gb (?), at well too? Or how would I command it to prune the data?
Depends.
The OS, Daedalus, and Cardano node version must all be identical. Note: the Vasil hard fork will likely require all nodes to re-sync and validate again so this isn’t the greatest time to be making a 100GB backup when 75% of it is about to become unusable. Currently there is no way that I know of to “prune” a full node so as the ledger increases so does the pain in setting up greenfield with a Cardano node for any purpose.
Related: Can immutable data on Daedalus be backed up and restored for quicker wallet installation/update? - Cardano Stack Exchange