Include CPT values in another CPT?

I’m trying to add CPT values in a drop-down menu within another CPT, not sure if this is do-able. Basically I have a Store CPT and a Manager CPT, in the manager cpt i have regular posts with the title, featured image, etc and what I would like to do is when I add a new store (on the Store CPT) i’d like to have a drop-down menu filled with the titles of Managers to be selected and associated, so that on the store page I can display the store manager as well.

A point in the right direction would be appriciated.

*CPT = Custom Post Type

Three suggestions:

1. Create Your Own Metabox

This is your original idea: when creating/editing the Store post type, the metabox will display a dropdown with all the available Managers of this post type.

For that, use Bainternet’s answer to this Question as a starting point, and change the get_categories for a get_posts of your CPT.
This will be stored as post meta and retrieved normally with a get_post_meta.

2. Use Post 2 Posts Plugin

^{wordpress.org/extend/plugins/posts-to-posts/}
I never really used this one, but I know it’s done for this kind of scenario and its author is a WordPress heavy weight…

In both plugin cases, read the documentation for the retrieval method.

3. Use Advanced Custom Fields Plugin

^{wordpress.org/extend/plugins/advanced-custom-fields/}
Another actively maintained plugin with plenty of custom fields goodies.

The field types Relationship or Post Object can be used for this purpose.

Bellow the screenshots of a test configuration using the post types Movies and Actors with a Relationship field (more complex than Post Object, which would produce a simple dropdown).

Field Configuration
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Field Result
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