Dr Michal Strahilevitz - from the University of Wollongong’s School of Management, Operations and Marketing - was a fan of bicycles until she had more than she knew what to do with so gave them away.

"There's a lot of joy when you add something to a collection," she said.

"It can be really fun, it becomes an adventure to look for something next for your collection, it can be a way to express yourself or express a passion for some type of thing - be it art or stained glass or ceramic cows."

Dr Strahilevitz has conducted research on consumer behaviour and said there were many motivations to collect but believed women were more likely to become collectors because they valued possessions they've had over time as compared to men.

She also noted that people could become very attached to possessions in a way that keeps them company, "it gives them some sense of comfort that 'this is my home'."

"I think it's like marking your territory in your own unique style or preference," Dr Strahilevitz said.

"I think collecting is one of those things that can be quite wonderful as a hobby, as long as you don't get to the point where you're compulsively adding to the collection."

Three Illawarra residents we spoke to listed pure enjoyment as the main motivating factor for their extensive collections.

Graham Draper has always remembered having LEGO in his life “in some shape or form”. However, it has only been in recent years his passion was reignited, so much so he regularly travels overseas for the beloved little, colourful bricks.

"To be able to look at something and build it using LEGO as a medium … the imagination is endless, you can build whatever you want," he said.

"Putting shows [like the KidzWish Brick Spectacular] on and seeing the looks on young kids faces and being able to give back to charities is a huge reason why I also do it. It allows me to do something I love but it allows me to give back to other people."

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It wasn’t his children that reignited his love for Lego but instead his wife, who bought him his first project: the LEGO architecture set of the Imperial Hotel.

At the time, Mr Draper wasn’t overly impressed with the gift, but once he completed the replica building a sense of accomplishment came over him. It also helped kick a habit.

"Five years ago I gave up smoking and the bloke - I went to a hypnotist - he said ‘use your money for something you enjoy doing’," he said.

"That was all around the same time, so I spent my money on LEGO and it hasn’t stopped now."

Mr Draper now has a large room dedicated to his hobby with literally millions of pieces - either stored in boxes or presented as spectacular sculptures.

There are giant architectural pieces which took months to build alongside themed "minifigures", the Statue of Liberty and hundreds of other creations.

Mr Draper’s most prized pieces are a Star Fleet Voyager set he made when he was eight-years-old and a limited edition yellow truck he received when touring the LEGO factory in Denmark (the equivalent of Willy Wonka's chocolate factory).

Only 140 people are handpicked to go on the tour each year, something much coveted by fans, he said.

"Billund is the birthplace of LEGO … you go to places that you would never see, hidden off the street," Mr Draper said.

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"[Such as] The Vault - it's a room underneath the original founders house - which contains one set of every LEGO set ever produced ... it's sort of like an urban myth in the LEGO community but it does exist."

The enthusiasm for little bricks has flowed to Mr Draper's six-year-old son, who has the pleasure of accompanying his dad each year to visit one of the nine LEGO Lands around the world - this year it's Germany.

Cathleen Coulstock admits she used to collect “everything” but decided her house would soon be over-run if she continued on that path.

Much of her collections were sold before recently moving back home to the Illawarra except for Holden memorabilia, lion and tiger ornaments, and an extensive collection of uranium glass.

Uranium glass is made with an additive to the glass mixture before melting for coloration. However, Ms Coulstock said it was decades before it’s greatest feature was realised: all are able to glow brightly under ultraviolet light.

“Someone potty in the 70s had their disco [and worked it out],” she laughed. “Apparently the early glass-blowers (because they used to blow all by hand) a lot of them died young from sicknesses."

Sometimes called “Vaseline glass”, it’s commonly a green to yellow in colour but also comes in hues of pink, blue, clear and red.

Ms Coulstock has cabinets full of ornaments, clocks, vases, serving bowls and dishes. Most pre-date World War II, some back to the late 1800’s.

"My nan used to collect, she always used to have bits and pieces around and I think that's sort of where I got it from," she said.

“I used to collect everything, but when I started collecting this it was like ‘if i’m going to collect this it needs to be just this, otherwise I’m going to have a house full'."

Much of her glass is sourced from overseas, mainly Europe, though many of her first bought items have since left her collection.

"Basic bowls and things that everyone's got, whereas I want stuff that’s harder to find … it just amazes me how much detail they could get into the glass," Ms Coulstock said.

After watching many episodes of Bargain Hunt, Ms Coulstock said a European trip was on the cards to search out more special pieces.

Long-time collector Barry* is a proud owner of multiple collections from novelty mugs, Disney memorabilia, dragons, board games, puzzles, movies, books, autographed celebrity pictures, movie posters, plus sci-fi and pop culture artifacts.

“Naturally there’d have to be some OCD in some way,” he joked.

Walking through Barry’s home you will find thousands of very proudly displayed items, polished and dusted, and grouped in their themes accordingly.

“I think I’m the the main collector, but I've got two daughters ... both girls are collectors as well,” he said.

Some of his most loved pieces include original crockery sets used on the Star Trek movie (picked up at one of many conventions he’s been to), a chunk of ancient Rome given to him from an archaeological dig and a piece of the Berlin wall.

"I picked this up just near the Brandenburg Gate in the early 1990s," Barry said of his piece of wall.

"There were a lot of people around at the time but no-one was picking anything up. It’s special, so I grabbed a piece."

Like our other collectors, Barry does it for the joy it gives him. He makes time to watch his movies, read his books and even belongs to a board game club so his artifacts continue to be put to good use.

*Surname has been omitted at the request of the interviewee.