See the previous reference with the link describing the anchorages
As a non-San Diego resident you have more options.
The A9 anchorage near the Coast Guard Station is decent but a bit isolated.
With a good dinghy
you could easily travel from A9 to dinghy dock
Exchange on Shelter Island Drive. From there the marine
businesses are close by - Marine Exchange, Downwind Marine, West Marine, etc. Post office, laundry
etc are all within walking distance.
Grocery stores are a bit further away. Vons at Liberty Station is probably the closest and best and Liberty Station has a number of other retail businesses - Trader Joes, etc.
If you have a military connection you may be able to land your dinghy at the marina on the Navy
base accros from Harbor Island.
On the weekend I would probably try to anchor
at La Playa as it puts you next to Shelter Island and you can shorter dinghy run then from A9.
Plenty of slips at the marinas
these days so you might be able to work a deal on a weekly slip rent.