I leased an aircraft his summer to do some hour building and managed to do over 100 hours in two months even when working two days a week. It's entirely possible to hour build in the UK, but probably only in the summer.
Leasing an aircraft is the best way to do it in this country as it is available to you all the time; no messing around with bookings and all the other disorganisation that happens at flight schools/clubs. For me, it also worked out cheaper than hiring from a club by a considerable margin.
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