is she cheating?

[in-a-tight-bind]

Two days after putting a deposit on a house I found some incriminating evidence that has led me to believe that partner is seeing someone else. She flatly denies it being any more than a friendship and innocent flirting, but I still doubt that she is telling the truth. I want to save our relationship and if she isn't seeing this person, don't want to ruin a relationship out of fear. We have 4 months before we take possession of our new home. She put up the deposit and upon my property selling we will add to the down payment. If we move in together and the relationship goes south, what am I entitled to? My portion of the down payment would likely be 3x what hers is... At this time we have no joint property as we aren't "technically" living together yet.

[standing on the sidelines]

Here is a good piece of advice, if at all possible get out of the deal with the house. If you have doubts about her cheating (or not) then moving in together is not a good idea. This is a two fold problem, either she is cheating or you are insecure in the relationship. No matter what the problem is, it has to be sorted out before you get that involved with buying property together. It is easier to get out of the relationship now if the problems cannot be sorted out. Once you sell your property and throw your money in with hers it will be a lot harder to end the relationship without a lot of grief.

[gondola_ride]

If she admits to flirting then that isn't good.

Either way if you do move in write up a legal document to stipulate how the equity would be split up if you did break up. I'm going through that now and wish I had such a document. If she won't do it don't move in. It is one of those hindsight 20-20 things.

[FL_Needs_To_Change]

I think a co-habitation agreement is the way to go.
If she is not guilty of anything she will sign without question.

If she is even remotely worried about her behaviour and her relationship with you she may hesitate.

Either way this will be a god sent should the worst happen