- How many locations are involved
- A single building is simpler to assess and pin than several sites intended to share related levels of access. Travel between locations, and keeping the hierarchy consistent across more than one property, both add to the overall scope of the project.
- Working around an occupied, operating property
- Rekeying doors in a planned sequence so a business keeps operating throughout, rather than all at once, takes coordination with the owner's schedule. Properties that need this staged approach, with interim arrangements for doors mid-conversion, add planning time beyond a straightforward, all-at-once installation.
- Compatibility of existing hardware
- Cylinders that can join the new hierarchy without modification keep the project smaller. Hardware that is mismatched, worn or built on an incompatible keyway needs replacing to fit cleanly into the plan, and that replacement hardware is a separate line from the design and pinning work.