A commercial building electrical inspection can be as simple or complex as defined in the scope of work between you and the client. It will all depend on the level of service they want and the information they want to obtain from the inspection. That being said, there is no boilerplate template out there that you can base all of your electrical inspection on and have it fit for all inspections.
Commercial buildings are going to range in size and use from a small storefront to large industrial complexes. Obviously the electrical systems are going to be significantly different from one end of the spectrum to the other. This is where a thorough understanding of the system you are inspecting is essential. You need to be able to walk through a property to define the scope of work and to outline what you will and will not being doing as part of the inspection.
Smaller properties can be a simple as doing a residential inspection, only with more panels to inspect. Larger properties may have switch gear components that will require a working knowledge to properly inspect. Industrial properties can and often have transformers in place that need to be inspected. If you are not qualified by definition to work on these types of components, then you should bring in extra help that knows what they are doing and can do it safely.
The biggest asset an inspector can offer a client is to provide a systematic view of the components inspected so that the work can be easily reproduced in the future by someone, hopefully yourself when the need arises. Electrical systems should be inspected annually at a minimum using thermal imaging. Typical things you would want to inspect for are thermal exceptions in panels and conductors. You should also include any voltage or amperage readings that you take during the process. Transformers should be inspected as well. This includes imaging the insulators and air switches. This is where knowing the limitations of thermal imaging and image temperature readings come into play. Your client may also have ground based transformers that are oil cooled. Your work scope may include taking samples for dissolved gas analysis and submitting the samples to a lab.
If there are not any plans available, it may be helpful to offer a plot of all the panels in the facility as part of your service so that appropriate maintenance records can be maintained from that point forward. Annual amperage readings should be recorded as well as component temperatures. This is setting the groundwork for trending data that can be used in the future for diagnostics or benchmark references.
As you can see there is no magic bullet inspection template out there. Your inspection will be unique to each property and client and can range tremendously in the amount of detail included. You MUST have a working knowledge of the system that you are inspecting. There is no guess work involved.