Generally, the type and condition of existing building walls determines if you can anchor the panels to the wall. The building wall must have sufficient strength to hold the anchors. A good rule of thumb is if in doubt, put a post at the wall. This will slightly increase the cost, but may save lots of aggravation and issues in the future.
• Drywall (sheet rock, gypsum board) walls usually require a post at the wall unless you can find a wall stud to anchor the panel.
• Cement block walls provide a solid, sturdy mounting surface.
• Wood walls, or wood strips mounted on walls make a fairly good mounting surface.
• Metal walls are usually too thin for mounting.