I’m a retired solicitor. I’ve been away and have just read this.
honeydo, your brother is totally incorrect in saying that the £175k allowance doesn’t apply. It does where, as here, an intestate estate is inherited by direct descendants such as you and your brother. This means that the threshold for payment of IHT is, in this case, £500k.
It’s vital that the value of the estate is correctly stated when an application for letters of administration is made. This includes not only what your mother owned when she died but also what she was owed (you said that money had been loaned to your brother) but gifts made within the last seven years; that includes the money spent on your brother’s brand new car and any other gifts she made. You need to see what money has been taken from her bank accounts over the last seven years in order to identify gifts - probably, from what you say, to your brother. IHT liability gradually decreases over the seven year period but such gifts cannot be ignored.
As regards the house, this has to be properly valued. Being of non-traditional construction will, as you know, affect its value.
Your brother is taking a very cavalier attitude towards valuing the estate, doubtless thinking that all tax and funeral and other expenses will be covered by your mother’s savings and as you expect nothing more than whatever cash is left you will be the loser and he will be sitting pretty in the house. From a legal perspective he could not be more wrong.
The estate, after payment of the expenses of the funeral, obtaining letters of administration and all ancillary expenses such as obtaining death certificates, falls to be divided equally between you.
Your brother is about to make a false declaration as to the value of your mother’s estate. It matters not that he is offering payment of IHT which is not due. You are fully aware of the intention to make a false declaration and you are thereby aiding and abetting him. That is a criminal offence. You must, without delay, see a solicitor to ensure that the application for letters of administration is correctly, not fraudulently, made in both your names, IHT is dealt with correctly and the estate, after any tax and relevant expenses as I have explained, equally divided between you . Don’t allow your brother to defraud you of your inheritance, allow you to bear costs which he should share or allow you to be complicit in his illegal statements and thereby incur criminal liability.
I can’t overemphasise how important it is that your mother’s estate is correctly dealt with and that no incorrect statements are knowingly made. Don’t allow your brother to let you get caught up in what he is doing. He simply considers that he will have the house and you the savings, less all the expenses. Go to a solicitor immediately to ensure you receive what is due to you. I suggest you show this to your husband, whose support you need and who would justifiably be very angry if your brother were to try to deprive you of your inheritance and at the same time embroil you in a deliberately fraudulent application to the court.