Well, to answer that question you need to know what most of these systems are based on.
Usually you will find that the majority of these systems are based on 'Loss Recovery'. What that means is, when you lose a bet you then try and win back the money you lost previously on the next race, repeating until you have made a profit.
On the face of it, that sounds like a sure way of making money, but what usually happens is you end up losing 10 bets in a row and the stakes get to a point where you are betting £1000's just to win £10 after recovering your losses. This is a VERY big risk and should never be used.
If you are considering buying a horse racing system on ebay the first thing you should ask the seller is 'Is the system based on loss recovery?', if the answer is Yes, then avoid like the plague as you are onto a sure fire losing system and could end up losing a LOT of money.
I have spent a considerable time looking at some of the horse racing systems that are out there and I can say that there are very few that actually produce any long term profits. There are some systems that work quite well but finding them is a long and usually expensive process.
My advice is to only buy a system that offers some sort of money back guarantee, but make sure the guarantee is not based on the assumption that you have £1Million to risk on betting. Always get a system that gives you a guarantee that you have a fair chance of winning in the long term with realistic profits.
Systems that say you will win £100,000 in 6 months etc are just crazy and should NEVER be purchased. You certainly wouldnt see a system like that being sold on ebay if someone was making that sort of money with it. Be realistic and expect to win small amounts with small stakes to start with and if any system can hold up in the long term it will allow you to increase your stakes and hopefully make a nice bit of money.
Anyway, I hope that has given you something to consider before parting with your hard earned money.
ALWAYS REMEMBER: Gambling is high risk and should be taken seriously, only risk money that you can afford to lose as this will take away any emotion and allow you to gamble with a clear mind.
Thanks for reading.