The combined forces of HMC&R, the UK Border Agency and the Post Office all collude together to squeeze as much out of us as they can in cases like this.
It's especially heinous on the part of the Post Office, who do absolutely NOTHING during the process except to charge their 'administration fee' for 'administration' which apparently consists of just charging the fee.
Not quite true, Kit. There's nothing sly or deceitful about customs charges so to use the word 'collusion' is misleading. The £15 de-minimis limit is there to avoid the public purse incurring the cost of collecting trivial amounts of tax - it's a concession, so somewhere a line has to be drawn.
As regards the Post Office, they have to prepare and lodge a computerised Customs Entry, notify the importer that a charge is due, collect that charge and pass it on to HMRC. The Post Office is run along commercial lines - being a Ltd Company as opposed to a Government Department - and the admin charge they make is commercial restitution for the services they provide. No "real" shipping agent would touch such small consignments for such a small fee.
If you wish to avoid paying these charges then either ensure that you order more than £15-worth of goods or source them from a UK supplier. In the case of the latter you'll still be paying the import costs, of course, although they will be hidden within the price you pay.
HMRC's website says that it will reimburse the cost of repairing or replacing items damaged during the course of inspection unless they are prohibited imports or otherwise subject to seizure.
DaveM