It's your deck. Tell them to make it 1 degree. And check a neighbor's deck as evidence of the correct slope. Tell them to match the norm.

It depends upon the desired speed of the run-off and the deck material and the comfort of use. Usually low slopes are seldom noticeable. A 45 degree or 12/12 slope on a deck sheds the water very well but effects the function of the deck.

What does the condo assoc. say about the slope? How much rain do you get? Exposure? What type of "deck"? What do the other condos decks look like? Their slope?

Noble has solutions that do not involve building a mud bed, and are the perfect slope. They will give you a parts list from a measured diagram, and have lots of support. Buy through your local distributor, usually Daltile. http://noblecompany.com/products/probase-ex/ 

http://noblecompany.com/storage/docs/resources/PX092023-03_Exterior_Deck_Systems_Design_Guide.pdf

That's a nice slope; I wouldn't worry about it.