If you're buying jointly then, because you previously owned a house, you will be jointly classed as non FTBs so you will be liable for 5% stamp duty in a house costing €310K. If she buys alone then she will be exempt from SD on a second hand house costing €317,500 or less. However if this sole ownership approach is merely to avoid SD and, in fact, you will actually be a joint beneficial owner then Revenue will probably have a problem with this:
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