My sister has been with her boyfriend for about 4 years, they live separately, he has one DC from a previous marriage..
They want to buy their own place together but in order to do that she is going to sell hers, move in with him into his house and then once a suitable house comes on the market they will only have one house to sell rather than 2.
They agreed to sell hers because his DC is settled in the house and it wouldn't be fair to move him once to hers, then again to another place, plus his DC can walk to school from where he lives now and can't from my sisters place.
Anyway, we were talking about it on the weekend and she plans to move in but not to contribute to the mortgage by paying rent, the reason being is that all her disposable income will go straight into savings and be used to put into the new house. She doesn't want to contribute to the mortgage because she won't be named on it so if anything were to happen to her DP she would need to leave and ultimately she has reduced someone else's debt with no benefit to her. Similarly if they were to split up she will have reduced her DP's mortgage debt and be entitled to nothing.
Her and her DP have spoken about this and whilst he agrees that this is the most sensible thing to do he keeps giving her the occasional dig, i don't think hes serious, but a lot of serious things are said in jest! saying things like "well you could swan off after a year of free rent with your savings" - obviously she wouldn't do this, unless the relationship broke down but she's concerned that it will start to become an issue the longer she is there.
She has asked me if its the right thing to do and I am biased because she's my sister and because this happened to me - I moved in with an ex, paid rent which reduced his mortgage so that when we bought our next house we would have had more of a deposit, but the relationship broke down and he ended up with approximately 20k reduced off his mortgage just from my contribution and I walked away with nothing.
So has anyone been in this situation? What did you do?