Add suffix to renting price

1.php

<?php
static function format_price( $price = '', $no_price_text = 'Contact for price' ) {
  	/**
		 * @var PGL_Options $pgl_options
		 */
		global $pgl_options;
		if ( ! $price ) {
			return apply_filters( 'estate/format_price/noprice', $no_price_text );
		}
		else {
			$symbol = PGL_Utilities::get_currency_symbol( $pgl_options->option( 'estate_currency' ) );
			global $post;
			$suffix = '';
			if (get_post_meta( $post->ID, 'estate_purpose', TRUE ) === 'rent') {
				$suffix = ' per Month';
			}

			return apply_filters( 'estate/format_price', ( $pgl_options->option( 'estate_currency_placement' ) == 'before' ) ? $symbol . ' ' . number_format( $price, 0, '.', ',' ) . $suffix : number_format( $price, 0, '.', ',' ) . ' ' . $symbol . $suffix);
		}
	}