Buyers could also break contracts if changes made to a proposed development were "likely to affect their enjoyment" of their future property.

Planning Minister Mick Gentleman presented laws to the ACT Legislative Assembly on Thursday to implement the first tranche of the government's strata reform package.

The reforms will deliver a fresh set of rules to govern apartment and mixed-use developments in the nation's capital. There were close to 58,500 residential and commercial units in the ACT as of September 1 this year.

The government announced the strata reform package in August, but Thursday marked the first time that detailed legislation had been made public.

MORE PROPERTY AND DEVELOPMENT NEWS:

Under one of the most significant changes, developers would be forced to include a "disclosure statement" in sale contracts, which would include an outline of floor plans, owners corporation rules and the method for dividing up levies among owners.

Buyers would have the power to break contracts if the seller amended some of the items in the statement.

For example, a buy could rip up a contract if the developer reduced their unit's size by five or more per cent, or the size of their planned balcony or courtyard by 10 per cent.

Alternatively, the buyer could continue with the contract and seek compensation for the change.

The Canberra Times this month reported that property industry figures were concerned that stricter disclosure requirements would expose developers to a greater financial risk.

Mr Gentleman said the first stage of the reforms would benefit residents and businesses occupying mixed-used complexes.