I could also recommend scanning through Airbnb. I've stayed in an apartment only 400m away from Bocadasee and it was fairly cheap.
I recommend one of the apt. rentals available thru VRBO or Airbnb near Bocadasse in Genova. It's easily accessible with public transit from all of Genova.
There are several little places along the water, look on trip advisor or booking com. I stayed in Genova and took a bus. It is fairly close so you can stay there and visit Boccadasse as well. Enjoy your trip
There are number very near along the waterfront where you can stay which are listed on tripadvisor if you google first.
The walk into Genova isn’t long so you can also stay centrally there too; or Taxi it if you prefer
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