Thanks for your answer - it's a tricky one and I am struggling with it - on the one hand I can see my partner's point of view as we are looking to having a future together. However, I'm the one putting all the collateral into the house and I can't get my head round why he should have the benefit of building up interest in a property that he has not contributed to. I guess, as you say, this needs to be resolved first!
Re the Declaration of Trust - how do I go about drawing up such a thing? Does this and a Cohabitation Agreement needs to be done through a solicitor and how water-tight is it? Are you confirming that a 'tenants in common' arrangement is not suitable in this situation?
Can this be done on-line ie via your service?
Pity! But your answers have been helpful so thank you.