17/01/2017 11:57 GMT | Updated 18/01/2018 05:12 GMT

Co-Habitation - So You've Bought The House, What Now?

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Boy meets girl. They fall in love. They live apart, spending their time between each other's flat, constantly packing and unpacking a bag. Eventually, they become tired of moving between flats and decide that it is time to move in together and perhaps even buy a flat.

Now, I have perhaps unfairly stripped out all of the romance but, in essence, this is a very familiar scenario, and one that millions of us have considered. In fact, unmarried cohabiting couples are now the fastest growing "family type" in the UK.

The problem with this scenario is that it's one of convenience (and hopefully romance): a lawyer's worst nightmare!

Understandably, very little thought is given to the "what ifs": "what if one of us dies" and "what if we break up", and no wonder. Moving in together should be an exciting new change, not a discussion about your impending breakup or death!

These are things that most of us would prefer not to talk about, along with pre-nups and even wills.

If this scenario rings a bell for you or a friend, what should you be thinking about?

The answer rather depends on the details. For those renting property, relax; beyond making sure you are not in breach of your lease, there is not much else to worry about.

For those buying together or where one of you is moving in to the other's flat, this is where the trouble can start.

"What if we break up?"

I have asked my family law colleague, Katie Spooner to help me with this one. She said:

"So many unmarried couples who cohabit are unaware of their limited rights. Our current law doesn't recognise a "common law" marriage, no matter how long you live together.

If two people buy property together, but are unmarried, the legal ownership of the property is usually dictated by the transfer deed that was signed when the property was purchased. If the couple then separate they will either need to sell the property and divide the equity in the way they agreed (under the terms of the transfer deed), or buy out the other's share.

The problem comes when you move into your partner's property and the property remains in their sole name or if one of you makes significantly higher financial contributions towards the property than the other that is not then reflected in the transfer deed (or in any subsequent formal agreement between you both). It is so important to remember that you do not obtain any legal rights or ownership over property as a result of your cohabitation, no matter how long that cohabitation lasts; even if for 20 years and you have children together. Neither do you require any automatic legal rights by making additional financial contributions to a jointly owned property.

Whether it be down to the throes of passion, lack of time, or inconvenience, people often fail to set out clearly with each other what their respective expectations are or their intentions regarding the ongoing ownership and/or interest in the property that has become their home. It is of no relevance that you may have been contributing to the household expenses and/or caring for the children if the transfer deed or other subsequent formal agreements (like cohabitation agreements) do not reflect these contributions."

"What if one of us dies?"

On death, the same strict property laws apply, so again the starting point is to look at the deeds.

Your executors (the individuals that will deal with your estate in the event of your death) would have the same limited and difficult claims that exist in your lifetime.

There is, however, one important difference: on death as opposed to separation, the law is more developed and, in certain situations, allows the surviving cohabitee to make a claim against your executors for "reasonable financial provision" from your assets. This is regardless of what you have included in your will.

The difference, of course and even if it seems a little macabre to say it, is that on your death you no longer need the assets. The result is that, in the eyes of those making the law, far fewer barriers exist when it comes to providing cohabitees with rights on death, as opposed to on separation.

What if I'd planned...

Whether it is on death or separation, dealing with these sorts of claims are so expensive and stressful.

It is true that if someone wants to cause trouble, they will always be able to do that. That said, so much of the cost, frustration and often anger can be avoided by talking about these things in advance. Yes, they are deeply unappealing topics of conversation for a married couple, never mind a couple that has just moved in together, but given death (and possibly, but hopefully not, separation) will happen to us all, the more we think and talk about them, generally the fewer issues arise.