Two years ago, the central Queensland town of Gladstone saw a property boom unlike anything in a generation.

Multi-million dollar liquefied natural gas processing plants were being built and turning nearby Curtis Island into Queensland's economic engine.

Some of the thousands of workers needed for the projects camped out in utes, parks and garages while they waited for properties to be built to meet demand.

Mum and dad investors like Nick Small, lured by brokers promising rivers of gold, wanted in.

Single father-of-three Nick was told if he bought a three-bedroom unit for about $550,000, he'd be getting $1000 a week rent and could expect to make about $6000 a year profit.

That was the case for about a year from mid-2011.

But a local real estate agency estimates about 3500 homes were being built in the region between 2011 and 2013, sending the town on a runaway path to over-supply.

By the time Nick got his keys last month, there was a glut of properties and workers had moved into newly-built camps or were choosing to fly in and fly out.

Nick's property is empty.

The best he can hope for is $500 a week rent.

If he sold, he'd lose at least $50,000 on his original investment just 18 months ago.

"I was a dumb country man, that's why I went to a broker for advice," he told AAP.

"I'm not quite sure they are predatory, not quite sure if they are cut throat, but they are there to make money.

"Inevitably they are my choices, it is my mistake."

The investment was supposed to be Nick's ticket to semi-retirement, but his plans have been put on hold until he can sell.

Ray White Gladstone estimates that in the first four months of 2013 there were 1740 properties in the Gladstone region on the market, which translated to 248 sales.

And, 530 homes are currently vacant.

The Real Estate Institute Queensland says 4.6 per cent of rental properties were vacant in June, the second highest level in the state.

One year ago, it was just two per cent.

Landlords are now offering fully-furnished homes, or rent free periods, to secure tenants. Some even chuck in free lawn mowing or a plasma television.

Ray White Gladstone principal Andrew Allen says a false market was created, and prices had consolidated in the last six months.

"We are the ones having to pick up the pieces when mum and dad investors come in asking why the rent isn't what they hoped for," he told AAP.

The Property Club has tracked boom-to-bust situations, and investors in Moranbah in central Queensland and Port Headland in Western Australia are experiencing similar hardships.

"Unfortunately, many mum and dad investors now face the very real possibility of negative equity and servicing huge loans and declining rental income," president Kevin Young says.

"Despite the new economic reality, property spruikers are still promoting new homes."

Gladstone Mayor Gail Sellers says locals are aware of the town's fickle boom and bust nature, something that was recently dramatised in community musical Boomtown.

Out-of-towners chasing a quick buck were most at risk, she says.

"I have to say I don't have a lot of sympathy," she told AAP.

"The people in Gladstone ... knew it would come to an end."