As long as you use one that specializes in Disney like
@Kingdom Konsultant then they are worth their weight in gold.
Booking a trip with my agent at KK consists of 2, maybe 3 emails at most. The first is me giving Marie (
@wannabeBelle ) my travel dates, resort choices, etc. She emails me back with the particulars and I tell her what to book. If I need her to reserve dining I give her that info as well.
That is it. I am done. The only thing I really have to do after booking is go on the trip. Everything else is taken care of.
Marie monitors all of Disney's promotions and automatically rebooks me if something better comes out. If something like my resort or my dates needs to be tweaked to get a promotion she will let me know what my options are and I can make the decision.
There is no checking for discounts daily. There is no getting up at 6:00 AM and pounding the phones if a promotion comes out. There is no getting up at 6:00 AM to do the same thing for dining.
Marie does all of that for the low, low price of $0. I can't imagine doing it any other way.