Can I install my own certificate in my store?
Based on the documentation I found, I think the answer is unfortunately no, but I thought I'd ask here to be sure. We are moving our store to its own domain and would like the entire site (not just the verification experience) to be SSL. Is there a way to install our own certificate for this?
Its not yet possible to use your own SSL certificate with Shopify. However, you have site-wide SSL / https support when using the https://YOUR-STORE.myshopify.com set of URLs.
Apart from the cost of the certificate and the CPU and network costs to run the entire site under https, I don't understand why you can't. Here's a post on this topic with more information: Using SSL Across Site
Shopify is a hosted platform. Buying an SSL certificate for your store is a waste of money. You cannot use it. Your domain name has zero impact on this.