For street parking
ordinarily the length is the pertinent question, and I think you are looking at the wrong model of Golf.
I think you are looking at the Golf estate of 4.6m, not the Golf hatchback of 4.2m . The Golf estate is a low seller, the hatch is the common seller.
(my opinion is that anyone who really wants a VW estate buys the Passat which is far better value in the VW models than the overpriced Golf estate; or the Skoda Octavia which although it is the Golf estate in disguise does manage to be cheaper and is noticeably larger)
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For driving the width tends to be the question. But as another poster has already pointed out, in the lanes that does tend to depend on whether you are prepared to jam your car into the vegetation of the hedge. The townies and posh cars won't, the locals will. Since we drive the old wrecks they are normally scared of us dinging their nice stuff, and they end up reversing to a passing point. Us locals just jam ourselves in the hedges and can squish past each other.
I'd love a model 3, but one day in my dreams when I do get one, I am wondering quite how the paintwork - and resale value - is going to respond to that sort of behavior.