If you have a weak PC, a love for retro aviation (1990s-2000s liveries), or simply don't want to spend $70 on a single MSFS airliner, the FS2004 addons freeware scene is your sanctuary.
: Renowned for highly detailed external models of Boeings and Airbuses. Users often download these for the visuals and then swap in more realistic third-party panels found on sites like Simviation Specialty Craft : Unique addons include the Mobile Control Tower
A great secondary source for rare European and South American liveries. Tips for Modern Systems