Assistance with Drupal Project

General information for the website: We are building out a large Drupal 8 project for a client and need an extra hand
Description of requirements/features: We need assistance with a couple of specific details related to our project:

1) Entity Feed: We need to connect an external data warehouse to the site and expose the fields as an entity that can then be used by views, and also attached to content types as an entity reference. The database content will be provided as JSON files, one with meta fields, and another with attached data. After an initial import, we need to be able to scan for only updates and modifications to the data feed. We are looking for the least complex and most secure way of achieving this and the first step will be brainstorming an approach with us.

2) We are using paragraph styles extensively, including several nested styles. In a couple of circumstances, we need some custom pre-processes and Twig modifications so these nested styles will display as designed. In one case, we have a paragraph style that uses several nested paragraph styles and displays them on a set of tabs. These need to be modified so they display the proper sets on each tab.

3) We have a couple of content types that require a couple of fields to display in a header region. We use a combination of pre-processes and Twig modifications to make this work, but a couple of fields need to be adjusted to display correctly (the full field with title is exposed as a single output, including the label).

Each of these are not overly complex, we just need a helping hand to get them completed within a very short timeframe (within a few weeks). The data feed is a top priority.

We will provide additional information and detail once an NDA is signed.
Specific technologies required: Drupal 8, JSON
Extra notes: We will provide access to a sandbox Git repo for the codebase, sample JSON files for setting up the feed, and the database.