The nice thing about pontoons is that because of their construction, there is one to fit anyone’s needs. When I bought my tritoon and was tossing around ideas on some mods, the dealer was ready to call up the head of the manufacturer to spec out a design and a cost. Want it a few feet longer? Just add a piece to the middle of each toon and extend the deck.
TMC out of Wisconsin and the one up in Grand Rapids are examples of factory-direct as well. No dealer in the mix.