Department / office setup
Booting entire new offices or departments is tricky because of the many facets involved, and esp. the communication needed. Viewed practically, the network infrastructure has to be setup / redesigned, often some on premise servers are needed, the regular office hardware has to be purchased and deployed etc. - but especially with new offices abroad, there’s more reasons to start planning a long time ahead: (foreign) regulations or language barriers can slow projects down. Not to mention the coordination + communication with partners that have as many different perspectives as project managers, architects, facility managers, finance officers etc.
Consultancy / Purchasing
Maintaining a good contact with key suppliers, evaluating which services are setup and maintained by which partners, researching new hardware and technologies - it's one of the most interesting parts of the job, for me. Especially systems for the audio-visual and 3D design fields are often challenging: software is developing rapidly; hardware can never be fast enough; APIs gain importance rapidly, in pace with cloud functions...