Hi, I have a question re inheritance.

A is a widower who is terminally ill and owns an apartment in Andalucia with his cohabitant B (50 % each). A and B are both pensioners and non-residents. No children on B's side. Five children on A's side, all of them Irish but two resides in the USA. No mortgage. A has no Irish will and no Spanish will. B has no Spanish will, but Irish will leaving the 50 % to A. Value approx. €450K.
Please answer the following:
1. Will the children eventually inherit 50% and if so will they have to pay IHT less €16K in Spain/Andalucia as they are non-resident?
2. Will anything change re answer in 1 if a Spanish will is made
3. What if B should die first and A still has no Spanish will?
4. Can A make a Spanish will without travelling to Spain?
5. A bit off topic, but how are a sale of the 50 % from B to A treated?
6. How will a sale effect the tax on a possible gain for the children and B?

Kind Regards,
R