Originally Posted by FLYMSY

Since you want to be in walking distance of the casino and FQ, you do have a wide variety of hotels to choose from. Try these:
Harrah’s hotel
Windsor Court
Sheraton on Canal Street
Marriott on Canal Street
Hilton Riverside

in the FQ:
Royal Sonesta
Hotel Monteleone
Omni Royal Orleans

There are a lot of other smaller hotels, also. It depends on your groups personal preferences. Check these out to see if they fit what you’re looking for, if not, come back to give more specifics.

edit: I’m not familiar with any Airbnbs in the French Quarter or CBD/Warehouse District (native New Orleanian & no need), however, my guess is that you would be hard pressed to find a decent place for $300/night for 3 bedrooms in these areas.