The good news about a sectional is that it comes apart. Once you separate the pieces at the connectors, you are just moving several manageable chairs instead of one enormous couch.
Pro tip: Sketch the sectional layout on your phone before you disassemble it so you can rebuild the exact configuration.
Watch out: Do not force pieces apart; if a connector resists, look for a release tab or lever rather than prying, which can crack the frame.