Thanks for your question.
If you are to own the property together you should specify to your conveyancer that you wish to own as tenants in common so that you can specify what proportions of the equity you own and that your interest will pass according to your Will (as opposed passing automatically to the survivor upon the death of the first to die).
At completion of the purchase you should execute a declaration of trust - this is a deed signed by both parties which specifies the percentage ownerships of the equity.
Alternatively you could just purchase in your sole name and if she does not contribute capital to the purchase, makes considerable mortgage repayments or makes other capital contributions to the property (eg. improvements) then she will not be able to make a claim on the house unless you have been married for a length of time.
Once you have been married for a considerable amount of time then parties are taken to have a 50:50 share in the combine matrimonial assets and liabilities of the married couple.
You can then execute a Will before you are married stating what is to happen to your share of the property upon your death. For example, you might give your partner the right to remain in the property after your death until she remarries or co-habits with another,
You can execute a pre-nuptial agreement specifying what is intended to happen to your respective assets upon separation or divorce and, although they are considered and Courts have recently been attaching more weight to their credibility in determining financial settlement, they are not water-tight enforceable as most may think.
They are worth doing though and to ensure enforceability you should both take independent legal advice on the agreement before executing.
In the final analysis though, it is part of marriage that ones personal assets become open to an element of risk once you have been married for a long time.
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