Drawing up a will via Solictor

I plan to contact a solicitor to draw up a will, but had a few questions in advance of doing so:

1. I need to nominate an executor, it will probably be a sister who won't be named in the will (as receiving anything) but one of her children would be. Is this allowed/recommended given potential for conflict.

2. Do you leave details of pensions from previous employers, accounts, investments etc. with solicitors or are these pieced together from my financial records in the event of my death.

3. Can I set provisions e.g. that y gets x amount when he/she turns 18 for example.

1. Not a problem afaik. In fact, executor could be beneficiary but beneficiary cannot witness execution of your will.

2. Will operative from date of death. You will need to give details of assets, liabilities etc. to assist in drafting up the will and consideration of any inheritance tax issues; but executor will ascertain actual position of estate at time of death (always useful to maintain some form of statement of affairs which is updated periodically).

3. Yes.