"It's every New Zealand skateboarder's dream. I'll be able to watch them, socialise, skate with them and ask them questions."
He wouldn't have won without the support of friends and family, and he also wanted to thank his two main sponsors, Supra (for footwear) and DGK for clothing. He found sponsors by sending out videos of himself skating.
Mr Marshall was a Castlecliff boy who started skateboarding at five, influenced by his brother Toby, a cousin and friends. Instead of going to school he often went to the skatepark.
He won his first competition in Wanganui before he was 16.
James Blas, a noted skater and skatepark designer, took him to his first national competition in Auckland. He went to each one after that, and had some wins.
He was living "a teenager's life - skateboarding, doing naughty things, drinking" when his Southland uncle took him in and made him change his ways. He worked as a chef in Te Anau and Christchurch, skateboarding at the same time and entering skating competitions.
Still depressed at times after the death of a daughter at two years of age, he said skating helped him.
"It helps me feel free and fly like an eagle. It stops me thinking about all those negative things."
His brother Toby and other family members are The Black Trio. Mr Marshall does some busking himself and said music also made him feel better.
His next goal is to open, and teach at, an indoor skateboarding venue in his home town. "I just want to create a safe place for our youth, a second place they can call home.
"I will hopefully have that up and running by next year.
"I'm looking for funds at the moment."