Most folks have a hairy tale about flatmates. Housesharing is a rite of passage; an unfortunate by-product of being young, hopeful of the good in people, and unable to afford anything better. But in this current climate, housesharing has become less a rite of passage and more a necessary evil even as we move into our late 30s and 40s. Data from Eurostat shows that in 2014, 9.2 per cent of Irish households had three or more adults living in them (a rise from 7.7 per cent in 2013). And according to Daft.ie data, sharing ad listings have increased 2 per cent year on year. With the Rent-A-Room scheme tax-free rental income for those renting out a room being increased from €12,000 to €14,000, it’s safe to assume that the number of cohabitees in Ireland is set to rise.

Recently, a news story about an Irish landlord with 108 outlandish house rules (“must wear deodorant”) went viral, and with good reason. You might not have had it quite that tough, but chances are you’ve experienced similar. If you survived your student days without tales of cohabiting woe, you are either fortunate or you were the one unwittingly causing all the ire.

Down the years, I’ve collected a real rogue’s gallery of dastardly cohabitees. This was one-telly, two-channel land, and there were no smartphones or laptops to retreat behind. In college, there was the housemate who drank Bovril and forbade me to watch RTÉ’s late-night music programme No Disco (too loud). And it got worse from then on. There was the who loved nothing more of a Sunday morning than to shower – bathroom door flung open so he could hear the Ramones from his bedroom – with nothing but a friend and a cowboy hat for company. There was the woman who was particularly fond of her power drill (specifically, cranking it up at 3am to show post-pub visitors her DIY prowess). There was the man who miraculously appeared in the kitchen just as dinner was served, and remained well-fed throughout his tenancy despite not knowing a stock cube from a bag of sand. And finally, there was the woman who omitted to mention in her advert that she was looking for an in-house therapist, but definitely should have. Three days and nine bottles of wine in, I succumbed to the worst case of renter’s remorse I’ve ever had.

Pilfering milk

I admit I’ve hardly been without sin myself. I’ve pilfered milk, shirked the odd bill in my measly student days, thrown parties during exam time, and had a go on the drill at 3am myself. In one excruciating moment, I was caught by a flatmate doing my Iggy Pop impression in the mirror.

Housesharing is a weird kind of intimacy, when you think about it. Often, it’s about sharing our sanctuary – a space for the most private of behaviours – with others, mainly for financial reasons. And even when our hearts sink at the sound of a key scraping the front door lock, we keep up the pretence that we might ordinarily elect to spend time with these people.

Winning the hellish lottery of housemates is difficult. Once upon a time, I prided myself on being a sound judge of character but a decade of house-sharing has pretty much put paid to that idea. In my defense, though, the house-share interview is an exercise in pure deception. Everyone is on their best behavior on the casting couch: truths get stretched, lovers who might be around on weekends are not mentioned. It’s hard to foresee problems when everyone is putting their sanest foot forward. One wily bloke promised free shampoos and moisturiser, telling me he was a beauty journalist. I only realised after the empty moving van sped away that the freebies wouldn’t be forthcoming; he’d been a student on work placement at a magazine for that week only.

Go for dinner

I have little in the way of advice for anyone stuck in the badlands of flatsharing. Except maybe invoke a new rule to at least lessen the odds of getting caught out: go for dinner with any potential new cohabitees before finally sealing the deal.

See how they eat, how they treat waiters, how they act when the bill arrives, and how they act when a drink has been taken. It will tell you a lot more about a person than what they blather in a 20-minute interview.

Ground rules are a good idea too. Get a cleaner if finances allow – you will save yourself a fortune in headache tablets. And there’s no less edifying a game than Guess-the-Owner- of-the-Body-Hair-in-the-Plughole.

I’ve also found that when meeting potential flatmates, it’s not a bad idea to run like crazy from the person who claims they are “never around”.

“I’m always out and about, I love to party, and I know loads of people,” they will say. If they’re saying it, they’re almost certainly not doing it.

Likewise, beware of thinly veiled phrases in adverts such as “sociable group” (read: frat house), “owner-occupied” (you’ll never truly feel comfortable there, and forget about putting up any pictures) or “creative household” (tiresome hipster purgatory).

Some people are better than others at sharing their home. They enjoy the company, aren’t particularly fidgety about things rotting in the fridge, and are more suited to small talk. Sadly, there is only room enough in my apartment for me and my many neuroses. At least I have done enough field research to know that I’m best suited to living solo. I pay twice what my friends do on their living arrangements, but still. My fridge can be a carnival of the fresh, the bad and the ugly, and no-one is any the wiser. And knowing that there won’t be a key scraping the lock at some point in the evening is priceless.