Joint mortgage, disproportionate deposit

[NerveAgent]

Me and my gf are looking into buying a house (ftb). She has some inheritance which will mean she can basically afford a 40% deposit on a nice place. I can never realistically match this without 10 years of saving and can only put in about 10%. My salary is pretty much double hers so the mortgage is reliant on me.

What do people do in these situation from a legal perspective? obviously she would want some kind of protection on her share but at the same time we dont want to count pennies.

[mcflurry]

Whatever you decide to do, get it signed and sealed before going ahead.
If the relationship goes sour, then it could be a nightmare to unwind (touch wood it won't)

(I would use say, the value of the house change divided by the percentage of the deposits + mortgage)

[MrChips]

Speak to your solicitor, as it's very common. You can do a "Declaration of trust" which basically sets out who retains what deposit etc if u sell the house.
It's unrelated as to why you sell the house so it doesn't get complicated.