Hi there, law student here. I'm assuming you're in England and/or Wales?

You should speak to a lawyer before you do anything, especially if you are the executor or personal representative. A lot will depend on the specific facts of your case and the results can be very different. As executor or administrator you might be legally responsible for administering the estate (paying your Dad's debts and other administrative expenses out of the succession estate before distributing the remainder).

Basically, debts are paid out of what is called the succession estate. Insurance policies paid straight to the beneficiary (i.e. your Mum) are generally not included. Those paid to the estate may be included, but this will be fact-specific.

Whether the house is included in the succession estate will largely depend on who owned the house and how it was owned. If you give him the documents relating to the house, a lawyer will be able to tell you whether it forms part of the succession estate (and debts paid out of its value). Unfortunately it may not be as simple as saying it was in both your parents names, all your names or indeed just your Dad's name.

If the house was owned in a certain way, then it may form part of your Dad's estate rather than pass straight to your Mum and so debts his debts may have to be paid out of it.

I'm sorry I can't be more specific. I would go and speak to a lawyer, most do free initial consultations where you can gauge what your position is. Make sure you bring along the Will, Death Certificate, the letters from the creditors as well as any documents relating to the house (Deeds, Official Copies etc).

(Disclaimer: this is not intended to be legal advice to be relied upon by anyone. Your position may vary enormously depending on the specific facts of your case. The above is merely to show how different the outcomes can be and that you shouldn't just rely on the advice of random strangers on the internet like me who don't know the detail of your case.)