We’re colocating with Equinix in Dublin.
We worked with a reseller to spec the hardware and have them shipped to the datacenter directly, and then Equinix Installation Services handled the actual rack & stack.
We’ve never actually touched the hardware, save one machine per rack: the install server. We had that shipped to a local employee’s location and they installed the OS which allowed us to use that machine to configure the networking and bootstrap all the others once it was installed at the DC.