I would like to emphasize the general details of this project for LEED v4 or v4.1 O+M certification.

There are 2 existing buildings (Building A and B) in a property boundary and these are industrial/manufacturing type of buildings including office/management in both buildings. It is under 1 single owner and management, and the 2 buildings are completely separate to each other with an enclosed connecting bridge in between with chilled water and power supply connection, though they have independent chillers and power distribution. Building A is an old facility since year 1998, while Building B is newly constructed and firstly occupied last 2015. The buildings are mostly monitored by a single management for energy, water, waste, there are shuttle buses serving occupants of both buildings, and they are sharing parking areas. The owner wants to achieve LEED Gold for their buildings.

May I ask what is the best approach to use in the project: Campus, Group, or Individual Certification and what may be the Pros/Cons/Challenges of each approach in achieving the goal?

Note: I also noticed in the Reference Guide that some prerequisites and credits say "Ineligible" if using Campus Approach, and "Submit separate documents for each building" if using Group Approach. What does it mean?