There are no hard and fast rules...a bbq can be as versitile as you want it to be, we simply sketched out on paper some different designs of how we wanted it to look then set about gathering materials. The stone was free, picked up from the local farmers field - doing the farmer a favour in the process. Then we built the base out of brick, bridged the top with off cuts of leftover steel rsj,s (although bricktiles would do the job just as well) concreted over the top then built the bbq "internal frame" which would house the firebricks (42 cents each)
After the "frame" was constructed we basicly built a stone wall around it and effectivly "shrouded" the bbq with natural stone. Being absolutley honest I had not planned this project with any amount of precision at all, it was a build it and see how it goes job, as for the grill we had one given but for around 12 euros your local welder could knock one up that will last for years, alternativly builders iron strengthening rods can be cut to size and laid side by side to create a rolling grill - this will be a modification we will make next summer.
So there we go, its a simple but practical design and blends in with our cave and the campo. Total cost around 35 euros.
Next....... laying a patio