Fresh plans drawn up suggest that homeowners may require consent from their local authority to convert properties.
Ministers launched a consultation on changing the planning laws following concern about the impact that the existing number of second homes is having on communities across Wales.
Dwyfor, which covers the Llyn Peninsula and the area west of Porthmadog, has been selected for a pilot area and £1m will be made available to purchase and refurbish vacant properties in the local area.
Climate change minister Julie James told MSs that Dwyfor had been chosen for a pilot which will launch in January with support from Gwynedd Council.
Two dedicated posts will support delivery of the pilot to link the interventions, engage with communities and maximise the impact.
There has long been concern that second homes price people in some parts of Wales out of buying property, particularly those living in communities in which the Welsh language is widely spoken.
The climate change minister has also launched a consultation on proposed planning changes.
This will seek views on the use of ‘class order’ in planning which would allow local planning authorities to require planning applications for additional second homes and short-term holiday lets in areas where they are causing significant difficulties for communities.
The consultation will shape the second phase of the pilot which could involve making changes to planning, taxation and tourism systems.
Speaking in the Senedd, James said: “We want young people to have a realistic prospect of buying or renting affordable homes in the places they have grown up so they can live and work in their local communities.
“High numbers of second and holiday homes in one area can threaten the Welsh language in its heartlands and affect the sustainability of some rural areas.
“We are a welcoming nation and tourism is a major part in our economy bringing jobs and income to many parts of Wales. But we don’t want ghost villages in seasonal holiday spots – places where no one’s at home in the winter months.
“These are complex issues and there are no quick fixes. What may be right for one community may not work for another. We will need to bring forward a range of actions, there is no one silver bullet here!”