How?
I've been sat looking into this for a couple of days.... Can you show me some figures please... or explain a little!
Here is what i came up with..
Vodafone
http://www.vodafone.co.uk/brands/iphone/pay-monthly-iphone/index.htm
12 months contract with vodafone
£41 per month.
500 mb
600 minutes
32gb phone £339
total cost £831
Actual monthly costs £69.25
Again sim only 12 months sim only with o2
£21.50 per month
500mb data
600 minutes
32gb phone £599
total £857
actual monthly cost £71.41
its cheaper to sign up with vodafone overall, yes its £41 per month, but overall its cheaper! you can still sell the phone on both contracts to get money back.... so I don't understand any other cheaper way... your getting the same minutes and everything!
In fact, if you paid £46 per month, you would get 900 minutes, and 750mb internet.. still for a total year cost of £831!
Well going on the cost above you want a 32GB for £599 get a giffgaff sim which is free, and for £10 a month you get unlimited ( yes, proper use as much as you want, no limit ) and unlimited texts, and 200 mins ( i feel like a giffgaff salesmen, i am reall not, just love it cos it's so cheap ! runs on the o2 network btw )
That works out at £710 over twelve months then sell the phone for approx £300 maybe more seeing its a 32GB and you have had an iPhone for 12 months and paid less approx £300
PS: just looked above, you're paying or looking at nearly £50 a month for a tariff? thats very hefty.