Mrs Bidois said the trust was working through a consent process with Rotorua Lakes Council.
But some residents were not responding positively to changes in management of the reserve after having a "free-for-all", she said.
"The majority of the things we want to do are around public safety and health and safety. We're working towards it, trying to get a handle on all of that, and it's a biggy.
"It's just that our community have had a free-for-all in Hamurana Springs [in the past] and they are not used to someone other than DoC [Department of Conservation] owning it. Most people are compliant, but some are ignoring the DoC guidelines and rules, regardless of whether we [are] there or not.
"We are new landlords, we have agreed to retain most, if not all, of the permitted activities that have been on the site. The trust will work from a legal perspective to make sure that we meet our legal obligations. But also that we're not limited by those obligations, which seems to be some people's focus - limiting what we are able to do, rather than supporting proactive ventures that will help pay for the place.
"We don't have deep pockets like DoC, we are just a little iwi," she said.
Hamurana Springs Incorporated Society spokesman Jerry Douglas said the group had been working with iwi and had no issues with management of the land.
"The iwi own the land.
"I am not concerned and I don't think other residents are," he said.
But a Hamurana resident, who did not want to be named, said she was concerned about the effect the cabins would have on the area.
"Four cabins parked on the edge of the carpark looks rough, "Where are they going to do their business? Are they going to walk all the way to the golf course or are they going to do it in the golf course?
"What is also a concern is people rinsing dishes, flies around scraps ... there's no water to these buildings. It's in the public interest; it would be okay if it was a nice building and it was ecologically attractive," she said.
Mrs Bidois said she was unsure about how changes in management would affect access to the reserve, although public access was guaranteed.
"We are working with DoC around people's interpretation of what all that [restrictions on access] means. Our legislation under the deed of settlement is to provide the public free access. What it doesn't define is how we manage that, so that is the challenge.
"One of the things we are seriously concerned about is most people don't understand that there is also a wildlife refuge on the river - that and boats up the river don't gel. Also swimming in the river is another non-permitted activity. There's lots of things that will definitely change ... over time."
