Measure the load before comparing boot space
A quoted luggage capacity does not tell you whether your particular load will fit.
A quoted luggage capacity does not tell you whether your particular load will fit. Measure the objects you carry before comparing the shape of a boot.
Choose the recurring load: a folded pushchair, work case or set of travel bags. Record dimensions in the configuration used for transport, including wheels and handles. Keep a simple drawing or cardboard template if it helps, but do not use a fragile or valuable item for an improvised fitting trial.
Measure the opening as well
Check the aperture, loading height and usable floor shape on the exact vehicle. A large internal space can have a narrow entrance. Include the seats in their required positions and any equipment that must remain in place. Follow the owner's manual for loading, restraint and permitted weights.
Ask permission before a demonstration and avoid blocking a showroom or roadside space. If you test a load, keep it secured appropriately and do not use the result to infer that the car can safely carry any weight that fits.
Record where the template met an obstruction and what would need to change. A useful comparison may favour a simpler opening over a larger advertised volume. The right question is whether the real load can be placed and carried safely in the arrangement you will use.