Budget documents say those changes alone will be worth about $25 million a year, or $109 million over the next four fiscal years.
Holiday houses, yachts, cars and planes will be affected.
Bookabach has about 5800 properties on its website, www.bookabach.co.nz, posted by the owners.
The business surveyed 200 members and initial responses from 160 owners found 70 per cent needed the extra income from rent because it made all the difference to their situation, Miles said.
"They said they would not be able to maintain a property without income," he said.
"Losing tax deductions means less money and it could quite possibly tip the balance for some people."
People logged into discussion site www.propertytalk.co.nz to complain of the changes, saying those seen to be rich were hit hardest.
BACH TAX
* 50,000 baches over 100,000km of coastline
* 5800 baches on bookabach
* 70 per cent of clients rely on rental income [Source: bookabach.co.nz]