1) Create websites from the front-end require the JMS 1.3 Full edition
2) You can create several JMS template rules corresponding to the different kind of website (or package) that you want to sale
3) Like in (2) this is you that create the website that are used as template to build the website from the front-end. So you can create personal website or ecommerce, ...
4) Yes this is what is illustrated in the tutorial video 14b, 14, 13b, 13
5) Idem (4)
6) I don't understand your question relative to "already translated to portuagese".
If you create a website template in portuguese, the website created from the front-end will be a copy of this one. So it will be in "portuguese".
If you want a translation of JMS in portuguese, there are some language file present in JMS for portuguese but they probably need to be update. The file were provided by customer but I am not sure they are complete.
7) Yes you can install JMS on existing Joomla website.
8) No there is no documentation in Portuguese - Only english is available.
9) I don't understand this question.
If you want to create a website from the front-end using a domain name instead of a subdomain or a subdirectory then you will have to setup your server to declare the domain name. Only the subdomain or subdirectories can be automatically created without any human intervention. In the case of a subdomain, it is require to use the VPS or dedicated server on which you have the "root" login to allow recompiling the apache to allow the automatic subdomain recognition.
10) In JMS, you can create JMS Template rule where you specify the "duration".
When the website expire, you can redirect the users to a specific URL.
11) This is good if you have a dedicated server or VPS with root login.
In particular if you want to have the automatic subdomain recognition.
12) If you want to create website where the customer enter the logo or other specific parameters when creating the website from the front-end, this is possible but require to create a specific JMS layout and specific plugin to manage those cases.
So this require a little specific development. We already did that for customers.
13) As emntioned in our home page, you can install JMS an unlimited number of times and also register it an unlimimted number of time.
So you can install it on a development environment, test environment, live environment, ...
14) The limit is mainly related to your server.
We alredy had case with more than 1,000 websites.
15) I can not reply to this question. This depends on each extensions.
16) The key element with template company is to identify if they are using their own framework to replace / bypass the Joomla framework.
Some companies may have issues that need to be patched.
This is for example the case of "Yoothemes" for which we have created a specific product because the repeat the bug in all the template, modules and component and they does not use a unique library for all the extensions.
What you are describing is something similar to
www.mywebsite2win.com where you can see different look of website and that customers can decide to buy.