Product research (Private labeling/Arbitrage)

I require an experienced freelance assistant with experience in amazon sales to help me set up an amazon sales business.
I want products and categories researching and advice on what products to source and where to source them from for selling in the UK. I want to use either Private Labelling (manufacturing ourselves in the UK or china) or arbitrage assistance.

Role 1: I am looking to manufacture a private label product and sell on amazon. I need you to research which category on amazon is safest (in terms of Amazon not annoyingly restricted products or categories) to sell in and what products are ranked well enough to manufacture (or ship) to the UK maybe from china, for me to then sell via Amazon in the UK or to wholesale in the UK. I want you to advise on the best categories to invest in and what products are manufacture-able and sell-able in the UK and are ranked well enough to sell. I want to know what well ranked products I can safely sell on Amazon with a reasonable ROI.

Role 2: Similar to Role 1 except that I want you to source ready made goods that I can acquire and sell on Amazon (rather than manufacturing them or importing them from china). These will be products that are ranked well enough on amazon to lower risk of us acquiring stock that is not selling. I want to know what well ranked products I can safely sell on Amazon with a reasonable ROI.