Need deck installed contiguous to existing deck. Must use 6X6 posts and is approx. 9 foot above ground. Must be solid enough to hold a Jacuzzi later if I want to get one. Size is approx. 15ft X 16 Ft. We will want 12" on center joists and will be covered with composite decking using concealed clips..Railing will be aluminum posts with glass and pickets (the brand is called Peak from Home Depot). I will buy all material and have on site but will expect contractor to provide a list of material to do the job for me to order.