1. A computer-implemented method for managing a target computing device, wherein the target computing device hosts one or more virtual machine instances, the method comprising: under control of one or more processors configured with specific executable instructions, obtaining, by a computing device management component, version information for software executing on a target computing device; determining, by the computing device management component, a distribution of modifications for a plurality of target computing devices based on the version information, wherein the plurality of target computing devices are arranged in one or more one host sets, wherein each host set comprises at least one target computing device of the plurality of target computing devices; for each of the target computing devices of a host set of the one or more host sets, prior to performing operations to prepare the target computing device to receive a scheduled modification, transmitting a pre-condition message to a client computing device indicating that the target computing device is scheduled to receive the scheduled modification; receiving a pre-condition response message from the client computing device with instructions on whether to proceed with the scheduled modification; based, at least in part, on the instructions received from the pre-condition response message, determining whether performing the scheduled modification on the target computing device exceeds a modification rate threshold of the host set, wherein the modification rate threshold defines a number of target computing devices within the host set that can receive the scheduled modification simultaneously; in response to determining that performing the scheduled modification on the target computing device does not exceed the modification rate threshold of the host set, preparing the target computing device to receive the scheduled modification by performing a pre-condition operation; prior to applying the scheduled modification, transmitting a pre-modification message to the client computing device indicating that the target computing device is prepared to receive the scheduled modification; receiving a pre-update response message from the client computing device with instructions on whether to apply the scheduled modification to the target computing device; transmitting a post-update message to the client computing device indicating that the target computing device received the scheduled modification, and performing a pre-condition cleanup operation on behalf of the target computing device.