I am considering buying a new extended cab. I've been driving around in a coupe the last few years and this would be my first truck purchase. Just tired of not having the power and room to tow and move things around. I like heading out doors and can't fit the gear into the truck. I'd want to customize the truck with some nerf bars or running boards and this is really where my question comes in. Should I buy these from the dealer or get them at a shop? What's the difference? Will the dealer offer the stuff that comes standard from the maker or are their more options? Basically, how does the purchase of exterior accessories for work? Thanks!!