Want to sell bullions online

I can reliably get gold coins/bars at very good prices and I have been arbitraging for small profits between precious metals dealers for over a year. So I want to write up a website similar to apmex .com or jmbullion .com etc to see if I can sell my stuff online. I can most likely beat their prices. I only want to focus on bullions so there won’t be that many products on my website. But I want the website to look cool/trustworthy. And I have some ideas to revolutionalize the industry (which will come after I become a traditional precious metals dealer, if ever) So an ecommerce website with product prices adjusting every minute according to spot prices. How difficult is it to write up? Possible to do it solo for a few months? What website frameworks do you recommend? I have done LAMP (Linux Apache MySQL Python) on AWS but are there any other frameworks you would recommend? Anything that’s reasonably scalable and can be done fast? TC 300K at Google right now. Not willing to give up my boring day job.