About 18 months ago I wrote about how you could sell access to Organic Groups with Drupal Commerce with a configuration of fields and Rules.
With Commerce License and Commerce License OG selling access to Organic Groups you have a setup that is as easy to setup than the 'old' field+Rules way (if not easier) and you'll have great new functionality for revoking membership access.
Step by Step instructions
You can find the step-by-step instruction on how to sell your Organic groups with Drupal Commerce based on Commerce Licenses at https://www.drupal.org/node/2366023. Just follow the 8 easy steps and you'll have it setup in no-time.
How does it work?
Basically you'll be selling licenses to your Organic Group (content). These licenses can expire, or be forever. You can configure them the way you see fit. The license determines if a user has access to the Organic Group or not.
Commerce License is a framework for selling access to local or remote resources.
Read more about Commerce Licenses at https://www.drupal.org/node/2039687 under Basic Concepts -> License.
If you follow the 8 steps in the instruction at https://www.drupal.org/node/2366023 you'll see that you can easily configure the products like this:
and users on the site will be given licenses like these:
From Dev to Stable
commerce_license_og module is currently in dev state. It works fine for the most common usecase: users buying access to your site. However make sure it works the way you want it before you decide go 'all in' implementing this on a production site.
Currently there seems to be an issue with granting anonymous users access to Organic Groups (https://www.drupal.org/node/2366155).
Please add your input to https://www.drupal.org/project/issues/commerce_license_og to help developing this module to a stable release.