The one-stop model is a contracting approach: a single provider takes responsibility for the whole project — each site’s local loop, the network (MPLS or SD-WAN), server hosting, and managed services (firewall, telephony, backup).
Its value: one contract, one SLA, one point of contact when something breaks — no more finger-pointing between the host, the carrier and the integrator. The ideal candidate is the integrated operator-host: it connects the whole territory, hosts in its own data centers and runs services in its backbone. Otherwise, a one-stop provider owns and displays the subcontracting of the lots it does not deliver itself.
The thing to check: that it actually covers every site and every lot — which is exactly what the DataColoc quote tests, line by line and site by site, to tell which partner can carry the entire demand.