I am expert in data crawling and had been crawling e-commerce websites from last two years. AMAZON is where I get started and I had crawled amazon for the information of products, category ranking, sellers data, reviews, best sellee ranking.
I can deliver you the task in least possible time, since we had been doing this for two years.
I recommend you to use any proxies solution as amazon has recently changed its bot detection mechanism and now they can track your IP quickly.
I would be doing this in Python+ Scrapy, and can embed crawlera(proxy solution) for you with no extra charges.
I can show you some of my current excel sheets, where we had extracted information of 10000 products on daily basis.
Besides code, I can help you in setting the environment on your machine, so with just 1 command, you can re started the process or add more brands and you DON'T HAVE TO PAY AGAIN.
PRICE CAN BE NEGOTIATED BUT YOUR REQUIREMENTS ARE NOT.