Is it really worth it?
In the version shown, without even getting into the required concrete footing, it has used approx 132 bricks, approx .2m cube of sand, a bag of cement, then adding the cost of the metal work, and the labour cost personal or otherwise to build it, you could easily buy several cheap BBQ's for cost of this one BBQ!
Another factor to consider, is that brick built BBQ's are invariably built in the wrong place, and with changes in wind and weather, become an expensive and very ugly garden feature.