WP Activity Log is a great security tool for any WordPress website because it tracks all activity within a WordPress site, including user-based activity (such as a certain user editing a post or page), plugin changes, file changes, and more. WP Activity Log also tracks activity outside of a WordPress site. The premium edition of the plugin extends the functionality of the free plugin by including additional features such as search and filtering capabilities for logs, email and SMS alerts, reports, and integrations with third-party services among other things.
Keep a log of file changes, Keep a log of REST API changes, Comprehensive activity logs, Activity logs for third party plugins
WP Activity Log Pricing: How much does the WP Acitivity Log costs?
WP Activity Log has 4 different kinds of pricing plans named Starter, Professional, Business and Enterprise. The price is $99, $139, $149 and $199 per year respectively. They also offer 14 days free trial and 30 days money back guarantee. You can choose the one fits for you.