It seems that one can only do 120 days a year of short term rentals, even if you have guests staying in a room in your home, your primary residence. That seems more restrictive than what is the case in any other major city.
Here's the good news:
The new rules have already been contested by the California Coastal Commission, which regulates hotels and other rental properties in designated coastal areas, including Venice. A lawyer who represents property owners told the Los Angeles Times that limiting rentals may violate the Coastal Act and plans to take the city to court.