Due to security reasons, not at this time but you can see all the inner workings of the theme in my instructional videos, if there's anything in particular you'd like to see open a chat with me (bottom right) and I'll help ya out!
Its a one-time purchase of only $59, that includes all the demos, the premium plugins ($70 value on their own) and 6-months of support which comes out to a $129 total value (which is steal of deal if you ask me).
Yes, I continually release new features, updates and fixes which are free for the lifetime of theme. If you have any new feature suggestions or enhancements to existing ones please open a chat, post them in the item comments.
Yes, modify it as much as you'd like! I've built it with ease of customization in mind — beyond the multitude of easy to use admin options you can take it a step further with a child theme and all the advanced hooks I've built into the theme throughout all the template files.
Yes, this theme has been designed & developed with SEO best practices in mind. I also recommend that you use one of the many WordPress SEO plugins available like Yoast SEO or All In One SEO to further enhance the search engine visability of your site.