A $122 MILLION outlay for a return of more than $1 billion seems a pretty solid investment.
And that's what the pundits predict will be the boost to the Australian economy across just three years if same-sex marriage gets the nod from the public and the parliament.
The winners, aside from the same-sex couples themselves, will be wedding industry figures including celebrants, florists, venue providers, jewellers, florists, hospitality workers and all those involved in pulling off a successful wedding celebration.
The loser? New Zealand, where more than half of the same sex couples who have married in the Shaky Isles since same-sex marriage became legal there in 2013 have been Aussies who can't do it in their own country.
The prediction is - should the $122 million same-sex marriage survey result in a Yes vote, and Prime Minister Malcolm Turnbull be able to deliver on his promise to legalise same-sex marriage by Christmas - it could be a wedding-heavy 2018.
And the wedding industry seems set for a tsunami of business as same-sex couples finally get the chance to open the purse strings for something they have either had to wait for, or head overseas to achieve.
COLD, HARD CASH
Anyone planning a wedding will tell you the figures are rubbery, and usually go up rather than down.
The same-sex wedding budget breakdown is no exception - even the predicted $1 billion boost to the economy figure is seen as conservative.
The ANZ Bank crunched the numbers in 2015 to come up with the $1 billion figure, predicting an annual boost to the national economy of $500 million due to nuptials alone, and spiralled that into a total economic benefit of up to $1 billion. The biggest beneficiaries? Small business and the service sector.
ANZ Bank economic researchers Cherelle Murphy and Mandeep Kaura forecast the economic benefits would flow thick and fast on the back of a law change.
"Marriage equality will be a fresh and much-needed source of demand for the Australian economy," their report said.
As well as traditional beneficiaries: retailers, hospitality and professional service businesses involved in the wedding and honeymoon industry, they said there were "additional economic benefits from an improved image of Australia as a more tolerant and progressive country."
The paper estimated up to 38,000 same-sex couples may get married if the law allowed, but based its figures on half of them tying the knot straight away and a quarter of them doing so within a year of laws changing.
"Based on an average spend per wedding of $51,000, that could add $500 million to $550 million to the economy in 12 months," the ANZ report said.
"If half of the population of same sex couples chose to marry within one year, the benefits to the economy in the first year of the legislation would be over $1 billion."
The figure's conservative, to say the least: the 2016 census found there were 46,774 same-sex couples living together in Australia, and over half would like to be legally married. That's more than 25,000 weddings which could be in the works.
And after the big day, there are indirect benefits - improved social, health and welfare outcomes - that would spill over into improved economic performance, the report said.
"The security that comes from a marriage would create an effective welfare safety net according to marriage equality lobby group, Australian Marriage Equality as spouses insure each other against a sudden loss of income," it said.
"It would also lower levels of stress and mental health problem which are indirect consequences of legal discrimination and social exclusion according to the lobby group."
WHAT THEY'LL PAY
The cost of the average wedding is hard to nail down - the ANZ survey used an average of $51,000, while Australian Securities and Investments Commission 2012 figures estimated it was $36,000. The reality is probably somewhere in between.
But Sydney-based marriage celebrant Stephen Lee, who has conducted commitment ceremonies for same-sex couples in Australia for the past five years, says one thing not in doubt is that there are plenty poised to spend.
"The average spend on a commitment ceremony would be about the same as a heterosexual wedding - start around $20,000 and just keep going upwards," he said.
"I don't know if it's a cliche to say this or not, but surveys show same-sex couples tend to have a little bit more disposable income than heterosexual couples, so they are prepared to dig a bit deeper for weddings. And especially, if they've waited for a long time, they are going to celebrate."
WHEN THEY'LL DO IT
If same-sex marriage is legal by Christmas, Mr Lee predicts two waves of weddings and "a brilliant 2018".
"There will be a peak first when the law change comes into effect; couples who have been together a long time or those couples who have big commitment ceremonies with family and friends already. They've done the big celebration and just want to go off and be legally married," he said.
"There are a lot of couples who have been together for 20 or 30 years that don't want the extravaganza of a wedding, they just want to be legally recognised. They feel married. They just want to go there and sign the forms in a very low key way.
"In the past couple of years I've done commitment ceremonies for people who say: 'Look, we'd love it to be legal marriage, but we can't put our lives on hold waiting for the law to change,' because life goes on. They will quickly do the legal paperwork."
The second wave, which Mr Lee estimates will happen from six to 12 months after same-sex laws take effect, will be the money-spinning tsunami.
"For all those couples who have been waiting, it's usually six months to a year in terms of venues being booked out and suppliers being scheduled in.
"That's when you'll see some serious, serious celebrations.
"It will be done with gusto, but then I think it will settle down and it will get to a point in a year's time when it's really no big deal and a point where you are marrying proportionally the same amount of same sex couples as you are heterosexual couples.
Mr Lee isn't the only celebrant who is fielding increasing inquiries from same-sex couples who believe a Yes vote win and a law change are near.
NEW ZEALAND NUPTIALS
If gay marriage becomes legal by Christmas, for the first time a "destination wedding" won't be the only thing on the agenda for same-sex couples..
No more will Aussie same-sex couples have to cross the ditch to get hitched.
Since New Zealand legalised same-sex marriage in 2013, it hasn't just been Kiwis taking advantage of the law change.
Last year, half of all same-sex marriages and civil unions registered in New Zealand were from overseas. Of those, a whopping 58 per cent were Australians tying the knot.
Mr Lee in the past year has hosted about eight commitment ceremonies for Australian same-sex couples who have married legally in New Zealand, but return to share the celebrations with friends and family on home soil.
"They hop on a plane, head to NZ for either a small legal marriage ceremony, then they hop a plane home for a big celebration and commitment ceremony," he said.
Mr Lee's done about 20 same sex ceremonies here in the past 18 months. "I expected there to be more, but I actually think there are a lot of people waiting, because marriage equality has been on the backburner for such a long time," he said.
"New Zealand will lose out if the law changes here. Their figures will see a sharp decline."
Same-sex marriage became legal in New Zealand on August 19, 2013
Nearly 1000 Australian same-sex couples have been married in New Zealand since 2013, making up a more than a quarter of same-sex marriages in the country.
Currently, five Australian states legally recognised same-sex marriages conducted in New Zealand.
New Zealand's same-sex tourism industry has grown as couples from overseas head to the country to marry.
Update your news preferences and get the latest news delivered to your inbox.