I’m not saying you should get married because you’d have to pay less tax, but I’m also not not saying you should get married because you’d have to pay less tax.Try it out on any tax calculator and you’ll see what I mean.Let’s consider Tony.Tony is 37 and living in sin with his other half, Carmela. Tony earns €50,000 a year. As a single person, Tony is looking at net earnings of €3,066 a month.If Tony were married, the money he takes home jumps to €3,353 due to the tax treatment of married couples.Sweet pay rise.It’s a considerable chunk of change. It’s also a wildly unromantic reason to get married, but the world needs pragmatists too.Of course, it also kicks in around mortgages and buying a house.Now, if you’re buying a house as a cohabiting couple, you’ve two options: a single or joint mortgage. All being fair, you’ll likely go with a joint mortgage, so both of your names are on the papers. Plus, with a joint mortgage, your earnings are added together and it’s easier to prove repayment potential.Part of the process of buying a house in Ireland is buying Mortgage Protection. It’s fairly straightforward: it’s a type of insurance you pay so that if you (or your other half) passes away, your mortgage will be cleared.Cohabiting or otherwise, you’ll have to get it. At least if you’re both on the books, you can halve the cost.I will say this: don’t let your bank bamboozle you into getting Mortgage Protection with your mortgage.The banks are tied to one insurer – but to get the best price, you should be looking at policies from ALL the insurers. Of course, you can also ask a friendly neighbourhood broker to do it for you. Much less of a headache – and less pocket ache as they can get you a better deal.