Some Australian real estate agents are updating their rental leases to stop tenants from secretly subletting properties on Airbnb.

Key points: Some real estate agents have updated leases to ban tenants from hosting through Airbnb

Some real estate agents have updated leases to ban tenants from hosting through Airbnb Landlords say Airbnb guests put extra wear and tear on their properties

Landlords say Airbnb guests put extra wear and tear on their properties Airbnb says renters and owners should have the right to share the home they live in

One lease, seen by the ABC, said the tenant must not use Airbnb without the "written consent" of the landlord in each instance.

Candice Deane, a senior property manager in Melbourne, said this clause gave landlords more protection.

Candice Deane has started inserting Airbnb clauses into leases. ( ABC News: Amy Bainbridge )

"Security and maintenance are the main issues, and if we approve that tenant, we want that person to be the person in the property," Ms Deane told the ABC.

"We discourage [sub-letting on Airbnb]. We don't motivate it and we don't want it to happen."

Ms Deane said in one case, she discovered a tenant was renting out an apartment on Airbnb while they were away on holidays.

"She was leaving keys in the mailbox for people to come and collect. So quite a few of the other occupants got really concerned about keys being left, who's getting them and what's going to happen to her apartment," Ms Deane said.

"She was also asked to leave."

In another instance, a Melbourne tenant was making thousands of dollars a month by hosting Airbnb guests full time in a leased apartment.

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A lease obtained by the ABC that includes a clause banning the tenant from putting the property on Airbnb without permission. ( ABC News: Amy Bainbridge )

Malcolm Gunning, president of the Real Estate Institute of Australia, said agents had been forced to take more control over sub-letting.

"It's primarily apartments where the biggest impact is, but even [for] a terrace house or home, the owner wants to know how many people are going to live in it because of the impact on the services," he said.

"If a property is really intended for two and you have six, that's three times the impact on the property itself. Water usage, the hydraulics, the sewage system, and just wear and tear in the house."

Malcolm Gunning, from the Real Estate Institute of Australia. ( ABC News: Rebecca Armitage )

Airbnb Australia's Brent Thomas said all people had a right to share the home they lived in, regardless of whether they were an owner or renter.

"Home sharing helps everyday Australians earn a little extra money to pay for their biggest expense — the cost of their housing," he told the ABC.

"We ask all hosts to certify they have permission to list their space and remind them to check and follow local rules before they list and throughout the year.

"A tenant who shares a spare room whilst they're living there or the whole home whilst they're away on holidays is actually a good use of their home."

Airbnb has an insurance program called Host Guarantee, which provides protection for up to $1 million for eligible hosts for damages.

Landlord says he'll insert 'Airbnb clause' into next lease

Sydney-based landlord Patrick Morrisey has leased out his rural property in the Byron Bay hinterland for the past few years.

His past two tenants sub-let rooms on Airbnb without his knowledge.

He said he was alarmed when he found out, because it raised liability issues and increased maintenance costs.

"The first time I visited, I saw a sign on the front fence and a new name had gone on the property. So I Googled that and it came up on Airbnb," he said.

"And with the second set of tenants, a friend of mine flicked me the page from the Airbnb site."

He said he set the rent so that local residents could afford to live there, and he did not intend for it to be run as a tourist operation.

"I found it quite distressing because the rent was really set at a price for affordable accommodation for locals, and those people were missing out on those opportunities because my tenant preferred to have tourists coming to stay on a one-nightly basis," Mr Morrisey said.

"I found it to be unfair and it put more risk on me as a landlord because we never had any discussions along those lines and they were doing things without permission."

He said once his current lease ended, he would take on a lease that specifically addressed Airbnb.

People 'should be able to make decisions about their housing'

Ned Cutcher from the Tenants Union of New South Wales believes a renter should be allowed to share their leased property on Airbnb — as long as they bear responsibility for any problems.

"It's the kind of decision a rational adult person should be able to make about their housing," Mr Cutcher said.

"The idea that because your household is established with a residential tenancy agreement rather than a mortgage, that you should somehow be restricted in the decisions that you can make is something that I struggle with."

Mr Cutcher said hosting an Airbnb guest was no different to a renter choosing to bring in a flatmate or sub-letting the property while on holidays.

"In Australia we have this idea that property equals wealth. And I think that it's fair enough that some tenants would want to try and tap into that a little bit as well," Mr Cutcher said.

"I don't see any kind of moral problem with a tenant seeking to profit from their interest in a property in the same way as anyone else would."

However, Mr Cutcher said he drew the line at tenants who leased a property to run as a full-time Airbnb without the knowledge of the owner.

"The idea that you're sharing available space while you're away is one thing. But if you've actually adopted a business model to extract the most value out of a property by letting it out on Airbnb, I do think that's a problem," he said.