The question I get most is whether a corner sofa will actually fit, or whether it just looks right in the showroom and then swallows a third of the living room once it is home. The honest answer is that it depends on the corner, not the sofa, and I say that as someone who measured a doorway wrong once and had the delivery guys standing on the porch for twenty minutes while I figured out if we were taking the door off its hinges.
Where it goes wrong is in a room that is already busy, lots of windows, a fireplace jutting out, a hallway cutting through one side. A corner sofa wants one clear wall and one clear corner to tuck into, and if you put it opposite a big window or across from another large piece, the room stops feeling like a place to sit and starts feeling like furniture storage. It also does not love a small square room, where it ends up eating the whole floor and leaving you edging around it like it's a parked car.
If you have never owned one, start plain. A cheap corner sofa in a trend color, with cushions that go flat by the second winter and a frame you can feel through the seat after a year, teaches you nothing except regret. A decent one, firm foam, a cover you can actually take off and wash, legs that don't wobble when a teenager flops down at the end, costs more up front and then quietly stops being a problem, which is the whole point. I had a cheap one for three years and every single guest who sat on it shifted around trying to find a comfortable spot, which is its own kind of feedback.
In an ordinary room it sits well with a rug that is big enough to run under the front legs, not a little island rug floating in the middle, and a coffee table set at a comfortable reach from the long side rather than jammed into the corner with it. A floor lamp behind the short end does more work than a second overhead light ever will. It also pairs fine with mismatched armchairs, you don't need everything from one set, the corner piece is doing the anchoring so the rest of the room can relax a little.
Measure the corner, not just the sofa, and go up one quality level from whatever you were about to buy.