Hi Sam and welcome to the forum,
In regards to Amazon, Sorry, but I have never been an Amazon seller and am a very long way from being an expert on their platform. So hopefully those with far more Amazon experience may be able to give you some advice on that.
In regards to how you get the best out of SaleHoo. We're a lot more than just a supplier directory, so if you're a new seller to the market you will find a wealth of information throughout the forum, as well as in out education section also.
In regards to selling, if you are finding that the competition is too stiff for you, then I would suggest reading this post and seeing if you can see any advantage in using the strategy outlined.
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