'For 3 years, I rented office space from a friend. Then I found out the truth.'

It was never part of my life plan to run a company with my husband. When we met, I worked in office administration for a legal firm, and he was a labourer for a company installing windows on new-build high-rises.

As we began to build a life together, Troy* wanted more for himself, deciding to use his years of experience to start his own window business.

At first, I helped him out with the administrative side of things in the evenings and on weekends. Eventually, as the business grew, I reduced my workweek to four days, dedicating the fifth day to helping him manage job bookings, stock ordering, staffing, and finances.

I continued to support Troy in running and growing the business while we started our family. After maternity leave, I never returned to the legal firm. Instead, I became a part-time employee of Troy's thriving business, which gave me the flexibility I needed as a working mum.

Troy was a natural, quickly gaining a reputation in the industry, and the jobs kept rolling in bigger sites, more employees, and steady work. All of this meant I was fast outgrowing the tiny office space in our home. It also meant I'd need to grow the admin team, as it was becoming far too much work for me to handle alone in the limited time I had.

Troy had rented a warehouse for the business, but it wasn't suitable for an office as well. So, I began searching for a space that would fit the bill.

I was at a friend's baby shower, catching up with my girls, when I mentioned my office search. My best friend squealed as an idea occurred to her. "I have spare rooms at my work, and I never use the upstairs kitchen. You could have that whole end - we could be office roomies!"

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Leah* ran a graphic design studio with a small team. She rented a large office space in a local industrial estate. Her offices were upstairs on a closed-off mezzanine level, while the large downstairs area was occupied by a printing company that had combined two warehouses.

The printing company used the office space at the other end and sublet Leah's end to her.

I went to take a look, and the setup was perfect. Leah's design team and I would have to share the bathroom, but I had an office, a small boardroom, and a kitchenette, all grouped together at one end, for my exclusive use. It was a dream. We set up a subletting contract, and I moved in with two admin assistants who job-shared a full-time role to help me out.

Leah wasn't concerned about a contract, but my years at the legal firm had taught me that everything was better in writing, always.

The printing company rented the entire space, Leah sublet the office space from them, and I sublet the rooms from Leah.

It was so great to have a professional space separate from home. Troy and I could switch off from work, which helped our marriage immensely. Plus, working so close to my bestie meant sneaky lunch breaks and the occasional quick drink after work, which gave me a reprieve from the monotony of life as a working mum. I loved it.

Time flew by, as it does, and we happily maintained this arrangement for nearly three years. Twice, Leah had to raise the rent, explaining that her own costs had increased. We set up new contracts, at my insistence, and carried on.

It all unravelled when the printing company decided to move out.

A real estate agent came through to take pictures for the listing. When the agent came upstairs to chat, Leah happened to be out at a meeting, so I spoke with him. He was trying to ascertain the details of Leah's contract and how it would impact the listing. He had spoken to the printing company and the industrial estate management team, but nobody seemed to know exactly how or to whom Leah was paying rent.

Confident it was a misunderstanding, I told him I'd have Leah contact him when she returned.

As it turned out, he was still downstairs taking pictures when Leah arrived. From my office window, I saw their animated conversation. Sensing Leah's distress, I went to meet her at the top of the stairs. She looked like she'd seen a ghost.

Close to tears, Leah barged past me with a flurry of excuses, grabbed a box of papers, and left as quickly as she'd arrived.

Slightly panicked, I called Troy, who came to meet me at the office. Together, we spoke with the printing company team, but they couldn't clarify anything. They gave us the landlord's number, and we promptly called. The landlord had no idea we even existed, let alone that we were subletting space in one of their properties, which made sense given the way our contracts were set up.

Leah's phone rang out repeatedly, and all Troy and I could do was go home with a looming sense of doom.

At 10:30 p.m., Leah called with her confession.

Leah had set up a handshake arrangement with the elderly former owner of the printing company when she first moved in. She'd done design work for him over the years, and he knew she was looking for space. Despite the area being too large for her needs, he gave her a good price and the keys. He emailed her an invoice for the rent each month, which she paid for a year and a half until he sold the company.

When the new owners took over, no rent invoices arrived, and Leah didn't push the issue. After several months, she realised she'd slipped through the cracks.

She'd been in the space rent-free for almost a year when I moved in. She'd been considering subletting her spare rooms but worried about getting caught as a squatter, so when I came along it was the perfect solution to her perfect crime.

Initially, she claimed she put aside the rent I was paying - which was more than her agreed price with the previous owner - as back pay in case anyone ever chased her for the owed rent.

As time went on, it became clear that nobody realised we were using the office spaces rent-free. The printers assumed we paid the management company, and the management company had no idea we were there.

I never found out what Leah did with the money, but over time I'd paid her more than $100,000.

I was so hurt - heartbroken, even. That anyone, let alone my best friend, would financially rip me off, put me in a legal bind, potentially ruin my family business, and strain my marriage was shocking.

Troy and I moved out immediately. I contacted my old firm to see where I stood, and thankfully, they were confident that the paper trail of rent payments and Leah's ludicrous price-increase contracts would cover us, though the situation was far from ideal.

Leah went completely underground. None of our friends heard from her, and her family remained tight-lipped about her whereabouts. She became a ghost.

For several months, Troy and I dealt with not only the stress of relocating our business headquarters but also the looming legal uncertainty. Combined with the heartache of betrayal, it was the most horrific time of my life.

We stayed in contact with both the printing company and the real estate management team, but nobody seemed to care about the situation as much as we did.

It's been several years now, and it seems Leah - now living on the other side of the country - got away with her squatting crime simply because nobody bothered to pursue her.

As for me, I came away with a new arsenal of trust issues - and an opening for a new best friend.

*Names have been changed due to privacy.

The author of this story is known to Mamamia but remained anonymous for privacy reasons.

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Feature image: Getty.