Westland District Property Ltd has spent $180,000 on the project so far and is budgeting to spend another $200,000 this year.
Westland district councillor Allen Hurley told the Otago Daily Times he wanted to know where the property company was getting the money.
He was concerned it could be ''selling off the family silver''.
''Have they got the mandate to do that?''At last month's council meeting, Cr Hurley said councillors were ''in the dark'' over progress on the investigations and he called for more council involvement in the project.
Cr Hurley told the ODT he would be raising his concerns again at the council's next meeting on February 28.
The property company announced in November it had signed a memorandum of understanding with overseas investors willing to put up $220 million to build a toll road through the remote corner of South Westland, to improve tourist links between the West Coast and Milford Sound.
Cr Hurley said councillors had not been told who the investors were.
''We have asked but they won't give it to us.''
Cr Hurley said he did not necessarily need to know who the investors were but he did want a breakdown on the cost of the road: ''basic stuff that the [council] should know and we just aren't getting the information''.
Cr Hurley said councillors also had not been given details of how the $180,000 had been spent.
''We keep asking questions but we keep getting fobbed off.''
An ODT request to council chief executive Tanya Winter for details on how the $180,000 had been spent was declined.
Ms Winter said she had been advised by the property company the spending details were ''commercially sensitive'' and if revealed could lead to the identification of the company's partner, which would be a breach of the company's memorandum of understanding.
Property company chairman Durham Havill said it had spent money on legal advice and ''looking at the whole opportunity''.
''Although it seems a lot of money, when you are looking at the complexity of something that hasn't been done in New Zealand, looking at the toll road, we welcome the investor but we also have to safeguard the territorial local authorities.
''So we have had to take quite a bit of advice on it.''
He said the overseas investors had spent ''a lot more than we have'' on such things as costing the road.
