Your head won't ache when the time comes to read your will. But you could be leaving a real and potentially costly headache for your heirs if you fail to make your wishes crystal clear, or if you have not bothered to appoint executors who are competent to administer your estate. You've just died. Your nephew claims you promised that after your death he could keep the prized classic car you kept in his garage. But your daughter and son-in-law are now threatening to take him to court unless he hands back the keys.

Ugly feuds between relatives grappling over inheritances is the stuff of soap operas. In real life, the beneficiaries of a will are rarely unprincipled vultures. Usually they just want to make sure a loved one's last wishes are carried out. But complications can arise after you die, so it is important to choose the right person as executor of your will.

Deciding just who that should be is not easy. The last thing you want is to burden the people you care about most with a protracted and complicated task when they're grieving.

The alternative is to appoint a professional - usually a bank or an individual solicitor. But letting these professionals siphon away some of your beneficiaries' inheritance in fees hardly seems kind either.

Many of the big names in banking are only too willing to act as executors.The appeal of appointing a bank to manage your affairs is in the institution's impartiality and trustworthiness, bankers say. If you feel your relatives are likely to squabble over your will, it might be easier to appoint a disinterested party as executor, rather than one of the beneficiaries themselves.

"People want the reassurance that things will be managed strictly according to their wishes," says Michael Bird, head of client services at BarclayTrust. Also, a bank can easily be sued if it makes a mistake.

But the service is far from free. Banks' charges are based not on time spent but on the value of the estate, and fees can eat up a sizeable chunk of the money you leave behind. On an estate worth pounds 100,000, Lloyds Bank would charge pounds 3,000 to act as executor, and add service fees on top of this depending on how many assets and debts are involved.

The Royal Bank of Scotland would charge pounds 4,000, but says it may vary these fees, charging more for a complex task or less for a simple one - particularly where the main asset is a house in which a surviving husband or wife will continue to live.

You can name a solicitor as your executor. In many cases, rather than claiming a percentage of the value of the estate, solicitors acting as executors will charge for the work involved. This makes it harder to gauge exactly how much the fees will be, but with a simple will it could be cheaper.

Julian Korn, partner at City solicitors Beachcroft Stanleys, recently charged pounds 750 plus VAT for acting as executor of a pounds 90,000 estate which had about three assets. If an estate of the same size had been complicated, this could have been as much as pounds 3,000 to pounds 4,000, he says.

But this is assuming the high hourly rates charged by central London firms. In the country, fees could be half these levels.

"Banks are likely to be less flexible than individuals, and they have charging structures which can be on the heavy side," Mr Korn says.

Apart from the cost, grieving relatives may find banks upsetting to deal with, says Tom Lemon, senior partner at Ealing-based solicitors Prince Evans. "The banks can be very impersonal ... and you don't get the feeling that they are involved," he says. Having a named solicitor as executor can help. "It's comforting to the individual to be able to sit for 20 minutes and talk about the person who has just died," Mr Lemon says.

But solicitors agree there's often no real advantage in naming a solicitor as executor. It could be better to appoint a close relative or friend as lay executor, who can in turn enlist a solicitor's services at the time if they feel they can't do it on their own.

This could even be cheaper, as it enables the lay executor to shop around when the time comes, and to do a portion of the work themselves. "A lot of people do find, when they are grieving, they don't want to be faced with a constant stream of letters - they would rather pass it on to someone else," says Mr Lemon.

But Peter Rodgers, who works in the City, acted as executor of his father's will 18 months ago and found having the extra work to do at a time of grief was not unwelcome. "It was rather a useful way of keeping my mind occupied," he says.

He found the task straightforward, and reckons he spent two days in total doing it. "With a simple will where there is a relatively small amount of money and it's to be distributed among a small number of people - it's a simple process," he says.

Mr Rodgers said he borrowed a book on how to be an executor. The main obstacle was getting the right forms from the probate office at Somerset House, though once he had them, he found they were very good and clear.

When you make a will you have to name between one and four executors. If you appoint two or more, this provides protection if one turns out to be unreliable, as decisions have to be made unanimously.

You should consider the following before naming someone: Is this person honest? Have they agreed to do the job? Are they likely to be around after you die?

Law Society: 0171-242 1222. Prince Evans: 0181-567 3477. Lloyds Bank: 0171-626 1500. BarclayTrust: 0171-403 4833. Beachcroft Stanleys: 0171- 242 1011.