If fitted by a company that does windows ,doors and conservatories then expect £500 + and probably not much under £1000 if in the south of England .
If you buy a door from the likes of Wickes and get a local fitter then it will be cheaper and possibly under £500 .
And go for a dearer rather than a cheapo one. the cheapo's are easily kicked in - especially the bottom panels. Dearer ones have a steel bar down the middle to deter break-in.
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If you buy a door from the likes of Wickes and get a local fitter then it will be cheaper and possibly under £500 .
UPVC door with an upper plain glass double glazed window, to include fitted catflap - £483.