American developer here.. I have sold products on Amazon for years. I can help you with this.
First thing though, you NEVER, want someone in a foreign country to log into your Amazon account. This can cause it to become locked for security reasons. also 50 products is very small, and helping you with that will be easy. Also, you will not have to pay me anything until I am done. My completion rate is 100% and I intend to keep it that way.