The 3 siblings are beneficially entitled to the property and CGT is charged on the disposal of beneficial ownership.
But consider whether they might be trading in land.
From the very limited information you have given, it seems that company A is acquiring your shares in company B, maybe for cash or an issue of shares in company A.
As company B would not be a party to such a transaction, why should it be liable for any legal costs???
Speak to your accountant.
No, if you read the thread you said "What if it was a bowling club" which is not telling us that it IS a bowling club.
You have still not told us what rights if any the club has that enable it to make use of the pub's bowling green. Until you give some kind of information about the current arrangements with the pub, no one can give you any guidance.
Getting information out of you is like extracting teeth. I'm out.
For Pete's sake tell us what kind of club this is! And also what right,if any, the club has over the accommodation!
From what you have said, the £20K to be received is not income. It is also not consideration for a supply, so no VAT. But CGT may be in point.
However there needs to be a disposal of an 'asset' which would include the disposal of a 'right' and you have not told us whether the club has any right to occupy part of the pub for its meetings or whether it is just an ad hoc arrangement. It could perhaps be that the £20K is simply a gift?
You clearly need professional advice on both the tax position and the apparent lack of a constitution.
No, if a return has been submitted for a particular year, a Sch 36 notice can only be issued if a s.9A enquiry has been opened into that year and has not been concluded see paras 21(1), (3) & (4).
Suggest you read the decision in Keith Hunter v HMRC.  UKFTT 0312.
You have not actually told us whether the income declared for 2016-17 was understated or not. Surely this is the first thing you should clarify with your client?
The redundancy pay was dealt with correctly as a non-taxable item. I think the problem lies within the Revenue's computer (or rather the lack of any 'sanity check'.
The problem was that she was placed on a K code which would have denied her any personal allowance and increased her taxable pay from the new employer by a notional £1669 per year.
Never mind the accounting treatment read up on the transactions in securities legislation especially IRC v Cleary
You haven't yet told us whether the business is continuing in different premises or whether business is being sold together with the assets. Until you do, no-one can tell whether entrepreneurs' relief is in point at all.