Melbourne City Council's response? After lengthy negotiations failed to move them, council contractors piled their meagre possessions on the back of a ute and drove off. Next, they installed planter boxes to stop the homeless coming back.

Many of the people camped there had serious mental health and drug issues. Others had dark, violent pasts: any city council would struggle to know how to act under these circumstances. But the solution resorted to was a telling signal of how this city council operates.

Rough sleepers like those evicted in May remain the most visible problem in a city that is, by most other measures, booming. The construction industry is buoyant. More than 30,000 international students are supporting a highly profitable city education sector.

On Wednesday, ballot papers for the election to decide who governs the world's most liveable city for the next four years started arriving in voters' mailboxes.

The surge in homelessness, perhaps the most pressing problem and certainly the most visible to Melbourne's citizens, however has been relegated to a minor role in the campaign for control of Town Hall, particularly for some of the highest profile lord mayoral candidates.

Seven are vying for the post, held by the Liberal Party's Robert Doyle since 2008, that is to be decided by October 22.

With most of his competitors preferencing against him, Doyle has nominated the Greens as his biggest threat, and observed that "elections are strange things – anyone who takes things for granted [can lose]".

This week, I spent some time talking to each of the serious candidates for lord mayor: incumbent Robert Doyle, planning chair and sitting councillor Ken Ong, Greens candidate Olivia Ball, pollster Gary Morgan, and former independent federal MP Phil Cleary.

Only two of them even thought to bring up homelessness during the course of our chats. One of them, the Greens' Olivia Ball, says over two months of doorknocking residents, homeless people are the issue brought up the most.

"People say 'I will vote for the person who is going to do the most for homelessness'. Rough sleeping … shocks people and they want something done about it." Ball compares education and health to housing. "No child will ever be denied a place in their local school. The same with health: no-one will ask how you will afford to pay for it. But we don't regard housing as a universal human right."

Cleary too brings up homelessness as a core issue in his campaign. "There is growing dislocation outside the city," says Cleary. "Youth unemployment, the cutback of resources in the hinterland, that's driving people into the the city, and what we're seeing inside is a reflection of what we are seeing outside the city."

Doyle talked of homelessness during his campaign launch and has led the council taskforce set up with the state government. The council has also brought forward funding for a Salvation Army drop-in centre and is considering at least $1 million more for a North Melbourne refuge.

But for something that even the council refers to in its communications as "a crisis", it seems curiously absent from lord mayoral campaigns thus far for Doyle and others (Ong, for instance, mentions it only in a response to a voter question in his campaign documents).

And homelessness is just one of the pressing big-picture dilemmas that really should be a source of ferocious debate in this campaign.

Instead, like other pressing agendas the city council could be a high-profile actor in – the state government's intention to funnel thousands of cars from Transurban's Western Distributor toll road into central Melbourne, or the failure of the booming apartment market to put a dent in housing affordability – it is all but missing from discussion.

There are now 134,000 voters on the electoral roll for Melbourne, up from 108,000 just four years ago when former Liberal planning minister Matthew Guy's skyscraper frenzy was hitting its stride.

Despite all the new apartments, however, just 55,000 voters live in Melbourne. The remaining 79,000 votes come from businesses which under the Bracks-era act establishing the city council get two votes to every one residential vote. It places pro-business candidates like Doyle ahead before a single vote is cast and puts progressive candidates like Ball and Cleary at a clear disadvantage.

Doyle proudly points to significant jobs growth in the central city over his time as mayor as an achievement that can't be ignored, with the revenue generated in Melbourne City Council's 38-square-kilometres going from $70 billion to $91 billion a year since he started in 2008. (Although council data shows gross local product was growing at roughly the same before Doyle arrived.)

He and other conservative candidates are less keen to discuss the downsides of the surge in skyscraper construction: darker, windier streets, congested roads in part from all the construction, or the precariousness of a building industry largely predicated on housing overseas students.

Like homelessness, the ultimate driver of this issue is not Town Hall – the planning minister approves all towers bigger than 25,000 square metres – but its effect is felt on the streets the council controls.

The Greens policies on planning are the most comprehensive released so far, and seek to tackle both affordability and the loss of "human scale" at the street level. Others, notably Ong and Gary Morgan, seem to have almost nothing to say about it.

Indeed, ask Ong about what he would do and it is almost as if he hasn't just spent his last four years chairing the council's all-important planning committee. "One of the key issues is looking at the ground level," he says during our talk this week. "We need to spend a bit more capital on street improvements and certain areas of the city where the footpaths are getting too narrow; the city safety needs improvement, lighting and too many areas are too dark."

Ong argued this week that, along with ditching the lord mayoral car, there should be a two-term cap on the number of times someone can be lord mayor – a none-too-subtle dig at Doyle. If Doyle wins, it will be his third term. If a lord mayor is in office too long, Ong says, "it becomes an empire".

As the incumbent, Doyle is used to attacks like this. "There are pluses and minuses to being lord mayor for eight years," he says. "[People] know what you stand for and how you operate. But because you make decisions, the more people you irritate."

Doyle says the Greens are his big threat, because of their success at harvesting preferences from the other candidates – including people like Ong who declared himself a "true Liberal" ticket, only to put the Greens ahead of Doyle.

Doyle says even if he wins more than 40 per cent of the primary vote (he won 41 per cent last time), having every serious candidate directing their preferences away from him could cause an upset.

But he says he has done enough to deserve re-election. "The jobs growth we have generated – the economic prosperity … is important," says Doyle.

Doyle's successful promotion of, and narrative for, Melbourne is a marked departure from the near incoherence of the John So days at Town Hall, when the leader was a figurehead unable to articulate where the city was headed, why, or how it would get there.

Doyle has been less keen to talk about one major issue over the last four years. It's an issue he freely admits The Age forced him to change his ways on: donations from property developers.

In 2012, Doyle took tens of thousands of dollars from developers – forcing him to sit out more than a dozen planning votes since because of conflicts of interest. He angrily rejects any suggestion he did anything wrong taking the 2012 donations, saying The Age blew the matter out of all proportion. "It's not about doing the right thing – I absolutely have."

But this time, under intense pressure over the issue, he is not taking money from property developers. It is worth pointing out that many of the developers who donated last time have flourished since, although there is no evidence the two are related.

Doyle also points to city safety during his years in office as a key achievement. It is borne out by last week's crime statistics that showed the total number of crimes fell by 0.5 per cent in postcode 3000. "That bucks the trend for the rest of metropolitan Melbourne," says Doyle, who on Thursday promised more city CCTV cameras if he is re-elected.

Phil Cleary's Town Hall campaign began because of another of Doyle's key battlegrounds: the $250 million Queen Victoria Market redevelopment. Cleary, a former independent federal MP, shops at the market, and traders upset at Town Hall implored him to run against the plan, which involves burying services underground and a major revamp, partly funded by construction of apartment towers on the market's southern borders.

Of the market traders he's supporting, he says: "I thought 'This group of people are quite magnificent'," and joined them in their campaign to stop Doyle.

Doyle says with frustration that the Queen Victoria Market plans have hardly come as a shock, even if they were always going to be contentious. The proposal has been widely discussed and voted upon since 2013. Political opportunism has brought people like Cleary out of the woodwork, he says.

"It has become a flashpoint," Doyle says. "I don't mind debating the ins and outs of the Queen Victoria Market deal, but it should be put in the context of a five year process, not an election."

But Cleary says to him the market is "emblematic of everything wrong with Melbourne City Council".

"Everything about it is completely mad. We bought the Mercat Hotel site at $76 million and then [the council] make a deal that you get an $80 million compensation if you don't go high enough?" (Under the plan approved by councillors, developer PDG Corporation gets $50 million to develop the Mercat Hotel site, if Planning Minister Richard Wynne approves a high-rise tower. If it there's no approval, PDG gets $80 million.)

"I see the Queen Victoria Market as emblematic of the way the mayor engages with the community," says Cleary. "It says we have got a serious problem here."

The candidates

Robert Doyle: Incumbent since 2008. Running for third term. Tarnished last time by taking campaign donations of $400,000 – including more than $40,000 from property developers. This time around he is not taking developer donations. Has been in office while city has flourished financially, while crime rates have remained steady or dropped. His big project is the $250 million Queen Victoria Market refurbishment.

Ken Ong: Planning chair for the last four years, Ong is independently wealthy from running a chain of childcare centres. In February he offered Robert Doyle a $200,000 donation to stand as his deputy, an offer Doyle declined. While Ong stands little chance of winning, he is passing the baton to Philip Le Liu, a fellow Liberal Party member, who recently stood for the federal seat of Melbourne.

Gary Morgan: A perennial lord mayoral candidate, the East Melbourne pollster has been virtually invisible this time around, and when he has surfaced, his venom against Robert Doyle has been noticeable. Believed to be running mostly as a means to get ally and lead council candidate Jackie Watts voted in for another four years.

Olivia Ball: The Greens candidate who ran against Bill Shorten in the federal seat of Maribyrnong recently. A human rights activist who has been strong on door-knocking but not outspoken thus far on city issues like planning and transport. If Doyle's primary vote goes down or preferences to the Greens are very strong, Ball stands a slim chance of being Melbourne's first female lord mayor in 27 years.

Ron Hunt: A Docklands resident and retired company director whose campaign is being managed by former Labor state MP Janice Munt. Hunt is understood to be running to help elect East Melbourne resident Robin Matthews as a councillor.

Anthony van der Craats: Van der Craats boasts he is a member of the Proportional Representation Society of Australia and views himself as a preference expert. A member of the ALP, he predicts Doyle will win in a landslide and says he is running mostly to hamper the Greens' chances.

Phil Cleary: Outspoken former federal MP campaigning predominantly against the Queen Victoria Market redevelopment. Also using the push to get a chance to talk about one of his key topics, violence against women (his sister was murdered in 1987 by her former partner), and issues like homelessness and "dogbox apartments".