Our detectives are back with the following intel on this WordPress site
The site is using two themes, one child and one parent. The child theme is based on the parent and often custom to the site. The parent theme is X theme by Themeco .
We could identify 10 plugins (there might be more) - Author hReview , convertplug , Cornerstone , Ninja Forms – The Easy and Powerful Forms Builder , revslider , Rich Reviews by Starfish , Yoast SEO , wp_estimation_form , WP Customer Reviews and x-email-mailchimp
Make all of your modifications to X in this child theme.