Authors Paul D Egan, Philip Soos and Lindsay David said they were concerned housing and taxation policy was being influenced by the heavy real estate interests of the parliamentarians from both major political parties, as well as minor parties and independents.

"The data demonstrates the majority of politicians have a vested interest in maintaining high housing and land prices, particularly the 76 per cent of members with one or more mortgages over their own investments," the authors wrote.

The LNP's Mrs Maddern, who on official records is listed under her first name Marguerete, has held the Fraser Coast seat of Maryborough since 2012 and leads the parliamentarian real estate charge with 12 investment properties, a residential holding and a commercial property.

Dr Bruce Flegg, dumped by the LNP as the member for Moggill in favour of another doctor, Christian Rowan, is next on the list, with seven investment properties in addition to his place of residence.

The new kid on the Labor block, maxillo-facial surgeon Anthony Lynham who was elected in last year's Stafford by-election, has an even split between investment properties and commercial or farm properties, with three in each category.