For commercial aircraft we assume that the aircraft has an interior in a typical airline configuration appropriate for its usage (i.e. a passenger aircraft should have seats, lavatories and galleys, but a cargo aircraft should have a cargo handling system, fire suppression system, etc.).
We do not adjust for passenger interior components on commercial aircraft because each airline has its own branding and layout and the buyer is likely to want to change the branding and configuration to be consistent with their fleet and their business model. We also do not adjust for IFE or broadband systems.
For Business Jet aircraft, we do adjust for a typical business configuration.