"Private landlords cannot be expected to subsidise the rising costs of letting," said the IPOA's Margaret McCormick.
"They have to cover their costs including heavy mortgages, try to earn a sustainable income and pay their taxes, just like everyone else. Private landlords are continually seen as easy pickings for the obsessive way in which the Government is seeking to raise revenue - but in the process, they are ignoring fairness and equity."
The latest "taxsault" is the double taxation applying this year in respect of the now abolished Non-Principal Private Residence (NPPR) charge and the new Local Property Tax (LPT).
The Minister for Finance told the Dail that LPT would be deductible against rental income, but then very quietly announced that it would be phased in "at some stage".
The IPOA said: "It is either a legitimate expense in the business of letting property, or it is not. It is a bit like a woman saying she is a little bit pregnant, or like the familiar saying attributed to St. Augustine: 'God, make me good - but not yet'".
The IPOA's Stephen Faughnan added that if it is a legitimate expense, it cannot be just phased in "as if it is some fantastic concession".
But the IPOA listed this as only the latest in a series of taxsaults "against all the rules of equity for private landlords"
This year, without any allowance against rental income, landlords had to pay one year's NPPR charge of E200 per unit of accommodation, followed by their own assessment of LPT - ostensibly to pay for the 'local services' which are enjoyed by the tenant. This is due to be followed again by a so far indeterminate amount in Water Charges from 2015 (but backdated to September 2014).
Mr Faughnan said: "We don't yet know how the water charges will be levied - or on whom in the case of rental property."