People don't understand what it costs to run a service plumbing cost. Its costs the company nearly 400$ just to show up at the door. Yeah, you can hire cheaper guys... which are probably unlicensed one man shops.
If you want your plumbing to be done the day you call, and you want a licensed guy then call the big companies. If you're on a budget, try your luck with someone else... although good luck if you need to pull a permit.