A group of residents asked the Audit Commission to investigate the Liberal Democrat council's sale of a garden centre in the 1980s.
Leading the fight, resident Anthony Berend said: 'Squires Garden Centre was sold for millions below its true value.'
The matter was investigated by the district auditor, which dismissed the allegations. Residents have now contacted the Audit Commission.
An Audit Commission spokeswoman said: 'The commission has received correspondence on this matter. It's not a case of a report being published. We will shortly be responding to any concerns raised.'
Richmond's Conservative group leader Tony Arbour said the garden centre was an example of political mismanagement.
'Richmond had a huge Lib Dem majority for 18 years,' he said. 'It's like the Labour rotten boroughs in the north-east. They just carry on in their own way.'
Labour group leader Michael Gold said: 'I'm glad the Audit Commission is investigating. Perhaps this will draw a line under it.'
Council leader Sir David Williams (Lib Dem) said: 'The district auditor said there was no case to answer. This is political mischief-making.'