A space can be linked to as many products as you like. Just select the space from the content page in any product you want connected to the space.
You can set the different pages to be viewable by different products. There are a few ways to do this.
1) You can set the pages to be auto-published and then release them who you desire when you desire.
2) You can control the access of a published page.
1. Go to the page
2. Go to the settings for that page
3. Set the page to be published
4. Scroll down to the section titled "Who should have access to this page?" Note if the page is not set to published you will not see this option.
5. Select the option "Only available to customers who purchased the following product(s)"
6. Select the paid product(s) you linked to the space.
7. Repeat steps 1-6 for each page that is paid content not being auto-published.