A political fundraising body linked to Tony Abbott was found to have financial discrepancies in the lead-up to the 2013 federal election and may have failed to declare gifts in kind, a critical report by the Australian Electoral Commission has found.

The Warringah Club – now known as the Sydney Small Business Club – is an associated entity linked to the Liberal party and the prime minister’s political fundraising. It has received thousands of dollars from the New South Wales Liberal party, as well as sent thousands to the party.

But the AEC raised concerns about the accounting practices of the entity in a compliance audit in February 2013 for the entity’s accounts year ending 2011, documents obtained by Guardian Australia under freedom of information laws show.

The audit identified problems with its accounting that led to an overstatement of both receipts and payments by $10,909. While clerical error was the reason given, the AEC report said the entity had provided no indication of how the error occurred.

“The discrepancies outlined in the report above are of some concern given the otherwise apparent professional approach to the record keeping undertaken by the financial controller of the Warringah Club,” the report said.

“While unspecified clerical error was quoted as the reason for the discrepancies, the inability of the financial controller to account for the error, particularly as he is a practising accountant, raises concerns about the approach to compiling the return in meeting the requirements of the [Commonwealth Electoral Act].”

Guardian Australia contacted accountant Peter Polgar, who is listed as the financial controller of the entity, but he did not respond to questions.

The audit also raised concerns about the possibility the entity may not have disclosed gifts in kind in the form of unpaid staff work.

The entity told the AEC “no paid staff are employed at all”. The AEC report said the “response implies, therefore, that whilst no paid services were made by the entity’s staff, some unpaid services may have been provided”.

“If this has been the case or is likely to be in the future, the value of the unpaid services provided by staff should be accounted for and reported as a gift.”

The entity was also late in providing key documents relating to gifts in kind, financial statements and loans, and did not provide working papers to support the figures reported in its returns, and the audit recommended the company remedy the discrepancies identified.

The prime minister’s office did not comment on the AEC audit.

The Warringah Club has previously come to public attention through its fundraising activities and political funding disclosures.

In April 2014 the NSW Liberal party also declared late a four-year-old $25,000 donation from the body. The declaration was among a tranche of amendments made declaring previously unreported donations over a span of years from different companies.

In 2010 the NSW electoral authority also found that the Warringah Club had broken NSW disclosure laws by failing to make required declarations.

Greens senator Lee Rhiannon has called for changes to federal electoral funding laws to improve transparency and reporting requirements.

“The inconsistencies and the discrepancies that the AEC has uncovered is a continuation of the problems with Warringah Club,” she said.

“It further underlines why we need uniform consistent electoral laws across the county. When it comes to associated entities they need to be required to have a more rigorous and transparent reporting regime.”