I want to migrate from Namo 2006 to CoffeeCup.
CoffeeCup's price list shows 31 items. Which of these would I need to buy to give me the same functionality as Namo 2006?

First tell us what Namo can do - or what you need to have done -, the we can suggest what Coffeecup products you need to achieve that.

Namo is very much like Dreamweaver. I have an older version (bought before I discovered Coffee Cup).
The HTML Editor would be the closest thing to it. But it really depends on whether you want a WYSIWYG or a code editor. If you're more visually inclined, the Visual Site Designer (VSD) might be more to your liking.
The additional software items can be added into VSD with no coding knowledge required - or used for convenience with the Editor (even if you do write your own code). You can also add other scripts and code snippets to either program.

Take advantage of the free trials and see what suits you best

What I do now:
I maintain a local historical preservation society site originally written in MS FrontPage (generally HTML which I am fairly fluent in). I was able to ftp download the whole site into Namo 2006 and then manage each page with Namo's range of options: WYSIWYG only, WYSIWYG and HTML, HTML only, with preview
I then have a range of ftp upload options.
BUT
They want the site completely rewritten with a different structure and prettier. Namo is very good on the re-structuring but seems very limited graphically wrt templates and themes.

I do not need/ cannot afford the likes of DreamWeaver. Which CoffeeCup apps would you suggest?

As paintbrush says: scan through the offerings of software that CC has listed on their site, and download the FREE trial version (FULLY FUNCTIONAL BTW!!!) of the ones that interest you. Play around with them and see which ones will be most helpful to your needs. Then back to CC site, to see which software bundle(s) have the best arrangement of those programs for your needs, and save a little $$$.