Condless

Limit the number of posts user can create. Any post type.
<a href="https://en.condless.com/user-posts-limit/" rel="nofollow ugc">Documentation</a> | <a href="https://en.condless.com/contact/" rel="nofollow ugc">Contact</a>
<h4>How To Use</h4>
<ol>
<li>Plugin Settings: Select role, post type, limit, and cycle.</li>
</ol>
<h4>How It Works</h4>
<ul>
<li>On post creation the number of posts from this post type belong to this user for the specified cycle will be counted and if applicable the post creation will be prevented.</li>
</ul>
<h4>Features</h4>
<ul>
<li>Post Creation Limits: Limit the number of posts each user role can create daily/weekly/monthly/yearly/ever.</li>
<li>Hide Content: In order to make some content hidden when posts limit exceeded wrap it with the shortcodes (replace "post" with the post type of the relevant rules): [upl_hide type="post"][/upl_hide]</li>
<li>Display Limits: Display the limits to the user anywhere with the [upl_limits] shortcode.</li>
<li>Users Stats: Track how many posts each user used from his quota.</li>
<li>Multisite: Network-wide rules can be applied via the Network Admin Dashboard (doesn’t support the Hide Content, Display Limits and Users Stats features).</li>
<li>Integrations: WooCommerce, Paid Memberships Pro, MyListing theme, Restrict Content Pro, PeepSo, WordPress REST API.</li>
<li>Limits per User: Set limits per user (see instructions in docs).</li>
</ul>

User Posts Limit

Отличный плагин

With a little elbow grease, the possibilities are really interesting for a multisite installation, such as limiting the total number of WooCommerce products per site (regardless of the author). The plugin is not easy to learn, not very intuitive and would surely deserve to be more explicit on certain settings, however, it does the job and the author is responsive and attentive… so I recommend it 👍 

Possibilities are really interesting for a multisite installation

Limit the number of posts user can create. Any post type.

Ryan Welcher

Patrick Rauland

This is a simple WordPress plugin which allows a site adminstrator to limit the number of widgets in a sidebar. You simply go the the settings -> limit widgets page and customize the maximum number of widgets used for each menu.
A nice visual effect will appear in the sidebar in the WordPress admin and the client will be unable to drop new widgets into the sidebar once the cap has been reached.
You can set widgets to have unlimited widgets by leaving the field blank. You can also set the sidebar to have 0 widgets effectively diabling it.
Credits
This is the Internet which means that nothing is created from scratch. This plugin is mostly a combination of work from other people which I just packaged into something with a user interface for easy management.
<ul>
<li><a href="http://wordpress.stackexchange.com/users/8/jan-fabry" rel="nofollow ugc">Jan Fabray</a> on <a href="http://wordpress.stackexchange.com/questions/19907/limit-number-of-widgets-in-sidebars" rel="nofollow ugc">WordPress Answers</a></li>
<li><a href="http://stackoverflow.com/users/821185/aman" rel="nofollow ugc">Aman</a> on <a href="http://stackoverflow.com/questions/6636701/limit-number-of-items-in-sortable-with-draggable-as-source/6663581#6663581" rel="nofollow ugc">Stack Overflow</a></li>
</ul>
Contributors Welcome
<ul>
<li>Submit a <a href="https://github.com/BFTrick/limit-widgets" rel="nofollow ugc">pull request on Github</a></li>
</ul>
Author
<ul>
<li><a href="http://www.patrickrauland.com" rel="nofollow ugc">Patrick Rauland</a></li>
<li><a href="http://www.ryanwelcher.com" rel="nofollow ugc">Ryan Welcher</a></li>
</ul>

Limit Widgets

A plugin for WordPress that limits the number of widgets in a sidebar.

User Posts Limit vs Limit Widgets