Is there a "template parameters" comparison chart?

I'm new here but understand a bit about website builders and software.

1. Before choosing a template is there a chart or table that compares the limits/features of templates or categories of templates, such as # of pages allowed, total file size restriction, max/min image dimensions, column/total widths, etc.? Is there a generic layout map with a filter function that describes all templates for instance to see "all templates with static left side navigation" or "all with a crumb trail?"

2. Can I begin to build the same presentation on 3-4 templates at once, so a comparison can be made as they progress?

3. Are templates simply about looks, with all at a given price level then sharing all technical functions? Or does chosing a template limit subsequent function?

If you are using Squarespace 7.1 (the newest version) every template has the exact same functionality.