Hi.As you are unmarried, if you own a property jointly which you let you are free to split the rental income in whatever proportions you like regardless of the ownership proportions. So, you could own a property on a 50:50 basis and your partner could disclose all the rental income as her own in her tax return with you disclosing no rental income. Take a look here for confirmation.If you make a gift of capital or assets with the intention of conferring a gratuitous benefit (see section 6 here), it will be a potentially exempt transfer for Inheritance Tax purposes. So long as you live for at least seven years after making the gift it will not be included in your estate for IHT purposes. Whilst you and your partner are unconnected, your intention would be to confer a benefit on her by gifting her cash to buy an income producing asset.Any gain you make from the disposal of a property has to be split in line with the ownership proportions.I hope this helps but let me know if you have any further questions.