What's the cheapest way to get an iphone 5s or 6 with unlimited data?

I've looked at pretty much everything lol. If not, does anyone know where I can find an unlocked iphone with a warranty?

The cheapest I've seen is probably straight talk. Its slower then other services from what I read, but you get what you pay for, its cheaper.

Pay monthly. Unlimited everything packages are usually available.

Get them free!