I primarily use Sponsored Products ads where I pay per click, but I totally ignore the suggested click prices and start at below half the suggested prices. I let it run for a few weeks to see which ones have the higher or lower ROAS and then make changes accordingly. In my opinion, anything with a ROAS less than four is just spending money to get it back. Focus on the keywords that provide the highest ROAS.

I only use coupons when I am looking to liquidate a product. Amazon charges a 60-cent fee for each coupon, so if I wanted to give $2 off, it actually costs $2.60, so I do this sparingly. I would consider using coupons to promote a new product, but I have had Amazon deny this due to a lack of existing sales, which makes no sense.

I have used Vine on a few product launches, but the results have been minimally helpful. You may end up with a few reviews, but you totally lose the whole value of the products you give away. You pay all the shipping, still give Amazon their payment of what they would have gotten if it were a paid sale, and pay Amazon a $70 to $200 fee on top of it. Ideally, a coupon would be more effective, but as I said, I had previously been denied coupons on new products. On average, I got seven reviews for every 10 products I gave away.

Overall, provide a quality product, work on building good descriptions, adding A+ content, maybe a few videos and do your best to ensure you describe the product well so you have less returns. And, with respect to returns, most of my bad reviews have been the result of people getting items that had been previously returned. If you opt to have Amazon evaluate and place a returned product back into stock, Amazon often just dumps the contents of what was returned to them, into a plastic bag, and ships it off to the next customer. That is a bad experience just waiting to happen. I have changed my returns to have the products liquidated or returned to me, but not to be resent to customers. My bad reviews have almost disappeared since then.

I hope this helped. Best of luck as well.