This place is OUTSTANDING. It has everything you need for a great stay at the beach - literally everything. Inside the house the host had thought of all possible supplies, from spices and cooking supplies to towels and laundry soap. It made our stay so easy. We stopped at Trader Joe's on the way for drinks and snacks (per Mark's suggestion) and were set to enjoy the beach the rest of the time.
As for outside supplies, this place had everything. Sun umbrellas (much needed), beach towels and toys, paddle boards (they are perfect for the harbor (which is only 30 seconds away) and BIKES. The bikes made our time so memorable. We took them out several times a day and used the bike path to explore Mission and Pacific Beach. He even provides a lock. We ate our meals outside on the patio, which is very private and free of traffic.
Now on to the location, it would be hard to find a better location in San Diego. Beach and bay were very walk-able, as were restaurants (both sit-down and counter service). We didn't go to Seaworld but enjoyed their fireworks multiple nights (just look on their website for times). Mission Beach offered volleyball (both to play and to watch), boogie boarding, sand dollar collecting and surfing. Such a clean, safe and wonderful environment for families.
I will be dreaming about my next visit. It was a great vacation!