Getting terms to have space between them

You can either concatenate your call to echo with a space or newline.

Space:

<?php $terms = get_the_terms($property['ID'], 'property_sub_type');

if(!empty($terms)){

    foreach($terms as $value){

        echo $value->name . " ";

    }

}

?> 

Newline:

<?php $terms = get_the_terms($property['ID'], 'property_sub_type');

if(!empty($terms)){

    foreach($terms as $value){

        echo $value->name . "\n";

    }

}

?>