Operating and maintenance costs are the other major component of TCO and are typically easier for OEMs to estimate. Operating expenses should include labor and the utilities/energy required to operate the equipment. As for maintenance, expenses that should be factored into TCO estimates include labor, replacement parts, and the necessary parts or tools. Assumptions will need to be made for maintenance intervals and durations and it is important to include the impact on production during the equipment downtimes for maintenance activities (i.e., lost production cost).
Various personnel costs may also need to be included in TCO calculations. While personnel costs may be categorized as acquisition or operating costs depending on the nature of the activity, it is important that OEMs account for these expenditures somewhere in the TCO estimate. Examples include time spent on purchasing (including research and vendor selection, order placement, expediting, and on-going vendor communications), logistics support, accounting, initial and on-going training for personnel as well as 3rd party or in-house technical support.