Be aware that Argos and Carphone Warehouse Sim free iPhones will lock to the network of the first sim used.
SIM-free iPhones

Would have to be off your head to trust eBay with an item like this.

Send me their seller page I want to see

Personally I might prefer to pay John Lewis £20 more for a "free" second year warranty (and less hassle if you change your mind - Argos are as bad as Currys at this!)....still - a reasonable deal from Argos!

Last two iPhones I bought recently off different ebayers had IPad mini serial numbers and they were ones with good feedback. Both said they were new made with bits when I complained!! Never again

​How are you so sure? Have you bought iPhone from them?

Paranoia. Plenty buy off eBay, I purchased countless phones off eBay since college, not one has blocked. Just need to look at the seller and their feedback...

Assuming you pay with Paypal of course, and don't paypal refuse a refund after 60 days or something?

http://www.bbc.co.uk/news/technology-39081895
Apple checking 'exploding' iPhone video

https://www.checkmend.com/uk/

If it comes up as dodgy on checkmend then get Paypal involved and you'll get the money back.

I used to buy iPhones off eBay and got good deals. These days too much agro with fraud, networked locked and iCloud locked. Also any EE phone sold within 6 months of contract start is stolen goods as they belong to EE for that period. It's expensive but I only buy new from big names now.

You can get these brand new off eBay and gumtree for around £450 for anyone wondering

£599 in JL with 2 yrs warranty. http://www.johnlewis.com/apple-iphone-7-ios-10-4-7-4g-lte-sim-free-32gb/p2999556?colour=Gold

I will ask JL to price match so get it at 2 yrs warranty with JL.

Same price at Tesco as well....

https://www.tesco.com/direct/iphone-7-32gb-black/226-7398.prd?skuId=226-7398&pageLevel=sku&icid=spiffy_iphone%207_226-7398_iphone%207

Be aware that Argos and Carphone Warehouse Sim free iPhones will lock to the network of the first sim used.
SIM-free iPhones

Looks like they no longer lock to the network of the 1st SIM used, it's been asked in the questions and answers section.

Hope this helps.

Been that price at Carphone warehouse for a while -

https://www.carphonewarehouse.com/apple/iphone-7.html#!colour=black&capacity=32GB&dealType=sf