"Then I hired my niece's boyfriend [Shannon Ripohau] and he's been with us for about nine years," Marshall said.
"We have 10 staff now and a six-wheeler truck, a digger, four utes, a stump grinder, a wood splitter, two chippers and two trucks for the chippers.
"When I started the business, I knew nothing about how to run it. I had to ask a friend's father how to do invoices. I used to throw the receipts in a box and throw them on the accountant's desk and run."
Along the way, Marshall married Siobhan and the couple has three children, Pani, 3, Haare, 2, and Ukupeau, 4 months.
When business started booming four years ago, Siobhan Marshall left her job at Work and Income and joined the team.
"We are in a really good place regarding training with a couple of our guys a few units off being fully qualified," Siobhan Marshall said.
"They are the ones doing the hard yards but we are supporting them through it."
She said they try to "give back" as much as possible and sponsor events such as Whanganui River food festivals and donate firewood to kaumatua.
The Marshalls are proud their business was a finalist in the 2017 Te Manu Atatū Māori Business Awards, receiving one of two highly commended awards in the service and trade category.
Lance Green, of Adept Accountants, has been on board since the beginning.
"It has been one of those unique journeys for an accountant where you see something start off and grow," Green said.
"We knew it had potential but we didn't think it would get to this size. It's been a big buzz for me."
Rivercity Tree Services' work covers a wide region from Taumarunui to Levin. They do work for a number of councils, roading contractors, schools and rental agencies as well as private clients and are planning to continue to expand the business.