The Scottish government has pledged to roll back changes MSPs made to its reforms of the planning system.
Ministers introduced legislation at Holyrood with the aim of streamlining planning and "empowering communities".
MSPs on the local government committee then made more than 230 amendments to the bill adding in extra powers and responsibilities for planning boards.
The government has warned these could "create millions of pounds of new costs" and undermine the legislation.
Local Government Minister Kevin Stewart said he was now working on fresh changes to "rescue" the bill and "remove unnecessary burdens" before MSPs vote on it for the final time.
But Labour's Monica Lennon said the government's approach was "timid" and would "plan Scotland's future on the cheap".
The Planning (Scotland) Bill was introduced by the government in a bid to overhaul the planning system, to "strengthen its contribution to inclusive growth, housing and infrastructure delivery and empowering communities".
However, all of Holyrood's opposition parties raised concerns about the original draft of the legislation, calling it a "missed opportunity", and set about making widespread changes in the local government committee.
More than 230 amendments were passed, many via contested votes which saw the SNP members defeated by the opposition. The changes voted through included:
- A requirement for people to get planning permission to convert a whole property into a short-term let
- A "land value capture" system to let councils benefit from increases in the value of land
- Requirements for planning authorities to consider the provision of public toilets, water refill stations and "play opportunities" for young people in local development plans
- Greater protection for music venues when new developments are planned nearby
In a new financial memorandum on the bill, the government warned that the changes made by the committee have "the potential to introduce further delays, costs and uncertainty into the system", and "could discourage investment in Scotland".
The memorandum claims the new duties introduced to the bill could increase costs to planning authorities by up to £75m, and cost businesses more than £400m.
Mr Stewart said: "Throughout the stage two process I made it clear that it wasn't simply amendments being added to the Bill, it was added costs, added bureaucracy.
"As things currently stand, we risk losing the savings that could have been achieved through streamlining, and creating millions of pounds of new costs for planning authorities. It is difficult to see who benefits from that.
"Many MSPs have indicated their willingness to work constructively to rescue this Bill, and I am grateful to those who have already engaged with me. Returning this bill to a shape that allows it to support inclusive growth will require co-operation."
However, Ms Lennon said she was "proud" of the amendments made, saying the government "wants to plan Scotland's future on the cheap".
She said: "Kevin Stewart needs to put his ego aside and think about what our communities need. MSPs challenged him to use planning to improve public health, ensure there are enough GPs, schools etc alongside new homes, and give communities rights and more influence. What a missed opportunity."