Thank you for your post. Map Store maps remain unlimited regardless of the subscription level (free, Plus or Pro), as the prices are set by the individual vendors that are hosting them. For custom maps, if you are using the free version of the app, you are limited to 3 active maps at a time. You can import as many as you would like, however, only the first 3 will be active.
There are a couple of ways to import multiple maps at once. The first is to use the Storage Locations import option to multi-select maps from either your device storage or another file-sharing system that you have installed on your device. The other option is to create a .avenzamaps file that allows you to list out the maps in a text-style file and bulk import them that way without the need to multi-select.
For more information on the .avenzamaps file, please see our help article available here
If you have any further questions, please don’t hesitate to reach out to us via support.avenzamaps.com and we’d be happy to help!