Known as rent bidding and deemed ‘‘totally unethical’’ by community housing organisations, the practise sees potential tenants taking part in an informal auction to see how much money they will pay to secure accommodation.

Tenants’ Union ACT executive officer Deborah Pippen said the practice is against the code of conduct for licensed real estate agents, but private advertisers aren’t held to the same standards.

‘‘From our perspective, rental bidding artificially inflates what a property is worth,’’ she said.

‘‘We condemn it.’’

Ms Pippen said rent bidding was a problem in Canberra several years ago and was concerned to be informed of a recent case, where an apartment in Bruce had initially been advertised at $400 a week.

After applying on Saturday, a potential tenant told the Canberra Times they received an email from the private vendor informing them of another applicant’s offer of $440.

The email went on to ask how much they and the other recipients would be willing to pay to secure the two bedroom apartment, which has attracted almost 800 screen views since being first advertised online a week ago.

The Canberra Times contacted the vendor, but no response has been received.

Ms Pippen said moves towards legislation preventing the practice were abandoned after coverage on the issue declined, despite still being labelled as unethical by agencies such as ACT Shelter.

Executive officer Leigh Watson said more than 1300 people were left homeless in the capital each night, the majority of which resorted to either couch surfing or crisis accommodation.

‘‘It doesn’t take much to draw a line between the increasingly high rents and the existence of those people on the margin,’’ she said.

‘‘With competition for affordable rental properties already fierce, behaviour such as this just pushes rental accessibility even further out of their reach.’’

Real Estate Institute of the ACT spokesman Craig Bright said the practice wasn’t condoned by agents in the local market, which has a current vacancy rate of 2.4 per cent.

Mr Bright said while the rate was considered normal, it could be skewed by the large number of properties coming on to the top end of the market.

‘‘It’s probably distorted that figure a bit,’’ he said.

‘‘I think if you took out some of those properties, that middle market would be quite tight.’’

Mr Bright said the market was due to tighten further in the approach to summer.

The incident comes as representatives from the community housing sector gather to discuss Canberra’s ‘‘housing crisis’’ this evening.