we did ensure that our mortgage was Tenants in Common with our individual contributions clearly defined, so that had it not worked out, we would at least have known where we stood financially.
This is what we're currently doing.
We've been together a number of years and lived 1/4 mile away from each other. After years of paying 2 x rent and bills, we decided it was stupid so started saving for a house, after getting a joint account a year or so ago.
In August we decided I'd give up my house and move in with him and we've had an offer accepted on a house so we're looking to exchange in Jan and (hopefully) complete late Jan / Feb.
Despite wanting to spend the rest of my life with my partner (I'm proposing to him on Boxing day!) We are both very practical, therefore will be drawing up wills, a mutual declaration of trust / tennants in common which defines what we've brought financially to the relationship.
And before we get married, we will get a pre-nup created.
I'd rather 'Have it and not need it, than need it and not have it' :)