Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
2. The value of the premises would be assessed and aggregated with his other assets for the calculation of IHT. IF the property is bequeathed to his wife or to a charity then it is outside the scope of IHT.
3. The percentage of the property owned by the deceased would be included in his IHT computation. See the note regarding spouse/charity in 2 above.
I do hope that you have found my reply of assistance.
The shares you hold in the limited company and your share of the LLP will be included in your estate for IHT purposes. However, the valuation thereof will be a complex and expensive exercise and gobble up the estate's funds to the detriment of the beneficiaries. I would be inclined to simplify the current structure whilst you still have time on your side. Anti avoidance legislation has largely nullified the 'leasehold carve up' as this practice was known. You would be well advised to take trusted, local professional advice regarding your situation which, on the face of it, appears over complicated.
Thank you for your suppert.