The long build-up to the NSW government's plans to merge the state's councils from a total of 150 to about 110 has initiated a process that some observers have dubbed "springtime for consultants".

Over two years, consultants have been paid hundreds of thousands of dollars by councils to model a range of hypothetical futures, many in an attempt to convince the government to spare them from the scalpel.

The state government, of course, has commissioned reports of its own. Its preferred firm, KPMG, has been paid more than $400,000 for analysis of its policy, which found it would reap a massive windfall of $2 billion in cost savings.

(Just how they got there, however, is a different story – much of the report's assumptions remain under wraps).

But Martin Bass, himself an independent consultant to local government, has come up with an interesting way to compare the way consultants approach a report, depending on who their client is.

He has compared a report prepared by KPMG for Bombala Council, which opposed being merged, with one prepared by the same firm for the state government, which argues mergers will be massively beneficial.

Below are some excerpts from the two reports, written six months apart - both comparing the effect of merging Bombala with two neighbouring councils in southern NSW.

Council: "The risks associated with merger implementation are high, with the prospect of high resistance to change within a merged council eroding potential benefits…"

State government: "The proposed merger has the potential to provide a $33 million benefit to communities over 20 years…"

Council:  "… a merged council is likely to materially underperform against benchmarks relating to asset renewal and infrastructure ... The merger business case suggests the major areas of efficiencies in amalgamation are non-frontline services."

State government: "The efficiencies and savings generated by the merger will allow the new council to invest in improved service levels and/or a greater range of services."

Council: "… a merged council entity may also encounter challenges in tailoring programs and initiatives to diverse community interests and profiles across a region spanning more than 15,000 km (squared)."

State government: "These communities are bound by their sense of place as an alpine region [… regional community services and organisations indicate] the existence of strong existing connections between the communities."

Council: "The assumptions adopted in the financial analysis are conservative and acknowledge the likely difficulties in generating efficiencies and economies of scale from the proposed merger."

State government: "This merger proposal will provide the new council with the opportunity to strengthen its balance sheet and provide a more consistent level of financial performance. Overall, the proposed merger is expected to enhance the financial sustainability of the new council."

The council-commissioned report also acknowledges something not emphasised in reams of state government-sponsored analysis: the evidence on whether council mergers save money is in fact mixed.

The council report cites research showing that fewer than one-third of Queensland council CEOs believed their councils would benefit after being merged and mixed anecdotal evidence from Victoria on the same question.

"I wanted to highlight the fact that you can present any scenario that you want to," Mr Bass said. "The real truth is that nobody knows what the degree of savings from mergers will be."

Mr Bass argues much of that comes down to very finely detailed particulars of how easily two councils can be merged in areas such as their IT systems, or their arrangements for paying staff; detail and potential pitfalls that, he argues, have not been given detailed consideration.

A KPMG spokesman noted both reports concluded that a merger would bring financial benefits.

"Each piece of analysis was prepared independently and relies on conservative assumptions," the spokesman said.

"The more recent analysis undertaken for the NSW government was able to draw on updated information on the reform process, including for example, greater clarity regarding the NSW government merger assistance to be offered to councils and the timeframe for reform."

In December, shortly before the second report was completed, the state government increased the financial assistance on offer to all merging councils from about $550 million to about $750 million.

You can find the council-commissioned report here, and the state government one here.