Buying an iPhone 6 Plus online?

Buying an iPhone 6 Plus online?

Added (1). have anyone tried this site?
http://appleoff.wix.com/appleoff#!price-list/czfo
it offers cheap apple products, but can I trust it?
how do I make sure it's not gonna rip me off?

please if anyone knows anything that can help me, answer as soon as possible

If the web site isn't apple.com, att.com, verizon.com, or sprint.com, I wouldn't trust it.

I wouldn't trust it. I'd just go through the proper, official avenues.