I'm currently looking at upgrading my existing amp (40watt Ashton combo) but I don't have a lot of money to spend, only about $600 Australian. So I'm going to have to buy a used amp. So far I haven't found too much in this price range (surprise surprise) and what I have found look like relics from the 50's that have been around the block a million times. Today I found a cheap amp and speaker cabinet at a place called 'Cash Converters' (a glorified pawn shop) for about $500. It looks alright but I didn't test it out. My question (and I do have one, bear with me) is what are some of the dangers of buying second hand equipment? What sort of things should I check for when buying it? If it sounds good and is in ok condition would it be worth parting with this money?