Hello, how do you do?
Without being told, I know you own an Amazon affiliate website. I own one too, and I've helped several clients write content and build their affiliate sites. First of all, I'll charge you $35 per 2500 words and this includes upload, inserting tables with TablePress, using the Shortcodes Ultimate plugin, inserting images and On-Page SEO for the article. I know you like 10Beast's format - I'll give you that.
I should also remind you that 2500 words take at least 3 days to finish. This will eliminate the possibility of errors in the article - making it professional enough to push you up the ranks in Google. I've placed a bid for $3000. This should cover the 50 articles you want to hire someone to write.
I propose this outline for the review articles which can be changed; introduction, table, review of the best tankless water heaters, buying guide, conclusions, FAQs. I've got samples of articles written in various niches for different clients for your viewing pleasure. Also, take a look at my profile page for reviews on Amazon affiliate articles.
Best wishes sir. I look forward to working on this project.