It could be better to see if any of his friends were musician types and let them do this. So much sound kit is publicly worthless despite being expensive to buy, but some bits and pieces are collectors items. I've told my son he must sell my guitar collection for their real prices and not what I told my wife I paid! Second best is the list here, it will be interesting though because of geographic differences. I'd love to see the list to see if the UK prices follow US? Maybe something is common and therefore cheap in the US but UK Ebay would get far more?