A clutch kit is not an expensive part. The reason a clutch replacement costs what it does is that the clutch lives between the engine and the gearbox, so the gearbox has to come out to reach it. You are paying for access, not for the component.
That is also why quotes vary so much. One garage quotes for the clutch kit. Another quotes for the clutch kit, the dual-mass flywheel and the slave cylinder that sits inside the bellhousing, because they know that leaving a tired one in there means taking the whole gearbox out again in a year.
The cheaper quote is not always the cheaper job. It is sometimes just the quote that has not mentioned the flywheel yet.
So we inspect first, and we price the flywheel and the hydraulics as separate, visible lines. If yours does not need them, you will not be charged for them.