The £250m figure includes the massive cost of machines to count votes with.Just like the ones they don't use in Australia.
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Rico,
Sat 16 Apr 2011, 18:59,
archived)
It also includes the cost of the referendum itself (£82m)It's all explained here: fullfact.org/blog/AV_referendum_cost_no_to_AV_yes_to_fairer_votes-2623
(,
Sat 16 Apr 2011, 20:36,
archived)