Among films with a rental rate of 4.99, what is the total number of films starred by Bob Fawcett?
Bob Fawcett' is a full name of an actor; full name refers to first_name, last_name
SELECT COUNT(T1.actor_id) FROM actor AS T1 INNER JOIN film_actor AS T2 ON T1.actor_id = T2.actor_id INNER JOIN film AS T3 ON T2.film_id = T3.film_id WHERE T3.rental_rate = 4.99 AND T1.first_name = 'Bob' AND T1.last_name = 'Fawcett'