Filter Default Estimation Fields

functions.php

<?php
function filter_si_submission_form_fields( $fields = array() ) {
	// Remove the budget field
	unset( $fields['budget'] );

	$fields['examples'] = array(
		'weight' => 120,
		'label' => __( 'Examples' ),
		'type' => 'textarea',
		'required' => TRUE,
		'placeholder' => 'Some examples of your request.'
	);
	return $fields;
}
add_filter( 'si_submission_form_fields', 'filter_si_submission_form_fields' );