Man robbed at gunpoint after placing phone ad

A Perth father is warning of the dangers of buy-and-sell websites, after he was allegedly robbed at gunpoint while trying to sell his iPhone.

Ikram Kahn, 32, invited two men into his Bennett Springs home last Thursday after they responded to his ad on Facebook Marketplace.

The father-of-two claims the fake buyers tricked his brother into leaving the room by asking for a glass of water, before one of them took off with the $700 phone.

Mr Khan says he held down the other thief, but his partner-in-crime came back with a gun.

"He pointed the gun at me and told me to leave his friend, and I just leave him, I didn't move," he said.

"My wife and my son saw the gun and they started crying. It was a really horrible situation."

He admits he didn't check the buyer's Facebook profile before agreeing to the sale, and it was deleted shortly after the robbery.

Police are appealing for anyone with dashcam footage to come forward.