Mallard is backing a call on the Welsh Government to partially remove a charge on people buying houses to let.
At present buyers have to pay an extra three per cent levy on their stamp duty – introduced last year by the former chancellor George Osborne – when purchasing a property to rent out.
A landlord group is hoping that the new Welsh Land Transition Tax (LTT), due to be introduced in 2018 to replace stamp duty in Wales, will remove the levy where a landlord is adding to the housing supply.
And that is backed by Mallard director Alun Thomas who says the current levy is having a major effect on the rental stock around the Llanelli and Ammanford areas.
“There has been a noticeable impact on the rental market because there are fewer investors because for the three per cent stamp duty levy,” he said.
“If some or all of that levy was removed it would release some of the financial pressure currently imposed on those choosing to buy to let.
“The rental market has been fairly buoyant in the area but it could be so much better.”
But the Welsh Government says the revenue made by the higher rate is “essential to the delivery of public services”.
The LTT was debated in the Assembly on Tuesday.
A Welsh Government spokeswoman said: “Respondents to our consultation about the higher rate expressed a clear view about the importance of maintaining a single, consistent rate across the UK when stamp duty is devolved to Wales in April 2018.”
The Residential Landlord Association (RLA) says a landlord buying an average-priced house in Wales (£147,000) to let now pays £4,850 in stamp duty, £4,410 more than under the previous system.