If you are cautious there are no problem, before buying always try to join the seller by phone/mail if the equipment is pricey just for enquire and check that there are no sting in the air...
Last week I just bought 2 Broncolor Verso power packs and 3 pulso heads for overall the 3rd of the brand new price, the seller was the owner of the equipment (very nice at phone

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So if you do the things properly eBay can be a big deal
