You can appoint anyone who is over the age of 18 and who has not been declared bankrupt. It makes sense to appoint someone living in the UK, and preferably, someone who lives close to you. The most important consideration is to appoint someone that you trust implicitly.
Your Attorneys are of course required to act in your best interests though sadly many all too many Attorneys abuse their position. That is why it is vital to appoint a trustworthy Attorney.
There is a two tier appointment with the option of appointing up to four attorneys on each tier. The first tier is made up of your preferred Attorneys and the second tier is your replacement attorneys who should act if the preferred Attorneys are unable or unwilling to act (or have died).
A couple with three grown up children may choose to appoint each other in the first instance as sole attorney. The three children may then be appointed as replacement attorneys and will only act in the event that the spouse or partner is unable or unwilling to do so.
If you appoint more than one attorney on either tier then you need to specify how they are to act. Must they act jointly so that they have to do absolutely everything together or can they act jointly and severally which means that they can act jointly should they wish but can also act independently? This latter appointment is favourable as a joint appointment can be far too restrictive.