Connolly suggested that the government could cut tax relief for people paying basic rate tax as well as high rate earners to give people buying their own home an advantage over investors.
Under the current system landlords can claim back up to 45% tax in mortgage interest costs, but by 2020 the amount claimed will be restricted to 20%.
Connolly and property analyst Kate Faulkner are currently in collaboration to research the merits of buy-to-let compared to other types of investment.
He said: “It wouldn’t be the greatest surprise if at some point all landlords were unable to offset mortgage interests against their income. It would be a dangerous strategy to do it in one go.
“The political way of doing it is in phases; so start with higher earners and widen it out.”
Faulkner agreed that the government has been clever by encouraging people to invest in other areas of the UK economy rather than property.
She said: “Restricting mortgage tax relief is going to cost some people thousands and most who invest in buy-to-let are high rate taxpayers.
“What they’ve done is make other forms of investment more attractive – it’s quite clever.
“20% of landlords currently don’t earn any income from buy-to-let, so by 2020 it’s going to be tough for them to break even.”
Connolly also reckoned too many people have used buy-to-let as a get rich quick scheme.
He added: “The government has been supportive of the residential property market but they also want to support people in buying their own homes.
“That’s more difficult when there are so many buy-to-let properties which have pushed property prices up over the years.
“I would argue that there are too many people looking to invest in buy-to-let.
“With the changes ahead I would warn people looking to invest in properties to do so with your eyes wide open.”
