Hire WordPress
A WordPress developer for the site you maintain.
Theme, content structure, and custom PHP when the site needs it, in the WordPress install you already have.
What this developer does for you
They work inside an existing WordPress site. The goal is a change the people who publish can still edit, not a new site that only the developer can touch.
Theme templates
Templates and styles in the theme the site already uses.
The way editors publish
Blocks or classic templates, matching how that site is built, so publishing does not become a developer task.
Custom PHP when the brief needs it
A plugin or theme PHP for behavior WordPress does not already give you. Not a plugin for its own sake.
A seat that can end
Month to month. Useful when the work is a build with a finish, and useful when it is ongoing care.
Will they rebuild the site?
The seat is for the WordPress site you have: theme, content structure, and custom PHP the brief names. A rebuild is a different brief, and the quote should say so.