Just because he pays child support he is not "buying" time with her. He is obligated to pay WEEKLY whether he sees her or not....when they garnish his wages and the $$ comes directly into your account, it won't be a JOKE.
if you do not need the $$ now , later on your daughter will....how much is college? a car down the road, car insurance, a new computer? a prom dress? BRACES? a trip with classmates.
think of the future and her insurance needs too. put the child support into an account.
like I said, assert yourself, he is wiping his feet on you trying to make you jump when he barks.