Ads - No 'Buy now' button

I am using version 7.1 but I notice that even the demo version on the Boonex site has the same problem.

Although I have checked the 'Enable Ability to work with Buy Now button in Ads:'  the 'Buy now' button never shows up.  Same problem with the Boonex demo site in the latest version.

Can someone please help me understand this?

Thanks

Do you have the payments module installed?

Have you set up a payment gateway?

Not sure if those things even matter... 

Three conditions must be satisfied for the button to show up.

a) You must be logged in.

b) You must be viewing an Ad that was not created by You. "Buy Now" will not appear when viewing your own Ads.

c) The "Enable Ability to work with Buy Now button in Ads" option must be turned on.