In United's innings openers Robbie Power (31) and Tom Lance (35) won the day, aided by 11 extras, to total 77 for none.
Central Districts Stags player Ben Smith was best of the Marist bowlers in his first club game in four seasons with 23 runs taken from his four overs.
United skipper Gerard Hobbs said his side was delighted to take the victory, but they knew that Marist were likely to bounce back.
"We bowled well and gained maximum points and that's great, but we are well aware they were down at least four or five of their main team and will be much harder next time," Hobbs said.
"They are a batting side, so it was handy to get them out cheaply."
Ross Kinnerley stood out in his first match for Tech (after defecting from Marist) when he took five wickets from his nine overs for just 20 runs to help his side beat Matt Burke Engineering Marton Saracens by five wickets. He was assisted by Caleb Greene and Nick Harding, who took two wickets each. Marton batsmen took 33 runs from Greene's 10 overs, while Harding was hit for 18 off four overs.
Tech captain Dominic Lock said it was Kinnerley's line and length that helped foil the opposition.
"It also helped they were down to 10 men. We made a few mistakes too, but we are very focused on winning this new competition," Lock said.
Try as he might, Marton captain Dom Rayner could not inspire his team despite top scoring with 40 not out. Ben McCallum (16) and Chris Rayner (10) were the only others to make double figures.
Tyler Lock top scored for Tech with the bat, racking up 34 runs before being bowled by Bryant Galpin. Kane Watkin chipped in with 19 not out, while Jess Watkin, who has been named in the New Zealand A team to play the White Ferns and Sri Lanka, scored 17 before being run out by Harding.
Dom Rayner claimed two for 22 from his seven overs, while McCallum took one for 21 off 6.5 overs and Phil Galpin one for eight off just two overs.
Meanwhile, Weraroa Senior A sit on four points after beating Kapiti Old Boys by 17 runs, but failing to score a bonus point.
AT A GLANCE:
- Bayer Marist: 75-8 (50 Over Match) (R Slight 5-18 ), Property Brokers United 1XI 77-0.
- Matt Burke Engineering Marton Saracens Premiers: 88-9 (50 Over Match) (R Kinnerly 5-20), St Johns Tech P1 92-5.
- Weraroa Cricket Club, Senior A: 96-10 (50 Over Match), Kapiti Old Boys CC, Senior A 79-10 (A Simonson 5-16 ).
- Paraparaumu Cricket Club, Senior 1st XI 15/16: 291-8 (50 Over Match), Levin Old Boys CC, LOB Senior A 142-10.