The first FAQ question addresses exactly that: colocation costs are added to every bare metal item (even storage drives).

Note that this doesn't intend to be used for accounting, but for estimating, and it's good at that. If anything, it's more favorable to the cloud (e.g, no egress costs).

If you're on the cloud right now and BMS shows you can save a lot of money, that's a good indicator to carefully research the subject.