I always get outbid on insanity dvds on ebay?

Ok so on ebay i wanted to get a cheap set of the insanity dvds and guides but I ALWAYS get outbid within 30 seconds to a minute and I was wondering if that is a scam or not? It happens on all of them not just from 1 seller but from multiple and idk what to do. Also if any of you know where I can get the whole insanity package (13 dvds and guides) for a really low price please tell me.