UK iphone 4 options

[tyranical]

Iphone 4 contracts

I'm just evaluating my options here, for the 3GS I went PAYG with £20/month simplicity as that worked out cheaper for me in the long run, I have been doing some calculations now for the iphone 4 and I just want people to have a look at them and see if i've gone wrong with them somewhere:

Contract

On a £40/month contract (you can upgrade after 16 months, with vodafone anyway hence why I've only done 16 months not 18)

£40/month x 16 = £640
£119 for the iphone
=£759

Sell my old iphone 3GS for £250ish
=£509
June 2011 the new iphone comes out, rather than waiting for the contract to finish, I'd buy the phone outright.

cost of new iphone = £500 (estimate)
=£1009

Money gained from selling old iphone 4 = £250 (estimate)
=£809

New iphone contract upgrade at the end of 16 months = £119 to buy the phone (estimate, may be less, my girlfriend just got £60 off the cost for already being a vodafone customer)
=£928

Sell 2nd hand iphone that I bought in June for £400 (estimate)

=£528 over 16 months.

Is all that right? have I missed anything out at all or c**ked it up?

Simplicity

Compare this to the simplicity calculations if i continued as I am:

Sell old iphone 3GS for £250ish

Buy new one for £500

£250 so spent so far.

£20 x 12 = £240
=£490

Cost of new iphone in June 2011 = £500
£990

Sell old iphone for £250 (estimate)

=£740 over 12 months

Are the above calculations correct in peoples eyes on here therefore showing that I would actually be much better off with a contract? Take into account things like costs of future iphone and costs of upgrades are purely estimations based on previous years, they're not going to be far wrong unless the next one is made of plutonium or something.

 

[Zcott]

It's probably easier to take out a simplicity contract and buy the new phone outright every year. That way you won't be tied into a contract for too long and you'll be able to have a new phone.

The downside is the initial expense of buying the phone outright but once you've done that one you'll never have to pay as much again (as all future phones will be subsidised by the sale of the old one).

 

[tyranical]

I have factored in the subsidised cost already as I bought my 3GS outright last year, I just want to know if those calculations are accurate or if I've missed something out or used the wrong figures.

 

[tyranical]

Come onnn, some kind soul out there with a mathematical brain in the UK (there are some believe it or not) must be able to look the figures over and see if they make sense.

I don't wanna go and get 1 on contract thinking woo i'm saving so much money only to find out later that its actually costing me an arm and a leg more and i've worked it out wrong.