Campsite in west Los Angeles

East Shore in San Dimas, Golden Shore in Long Beach. Both are in about the same boat price wise as Dockweiler and farther away. East Shore is fine, but a grind to the coast in traffic. I'd just go ahead and stay at Dockweiler again. Marina Del Rey is not particularly accessible to RV parks.

LA and inexpensive are two words that do go together. Find what you like and pay the price.

As others have said there is nothing inexpensive in the LA area. There is a park in Long Beach, Golden something I think. We've stayed at Walnut RV in Northridge, it's fine. Balboa/Birmingham in Van Nuys is junky. There's a KOA in Pomona and a Ventura County park (Tapo Canyon) in Simi Valley. Look at www.rvparkreviews for areas around there.

We stayed at a very nice campground in Pomona. I do not remember the name but I would use the site rvparkreviews to look at campgrounds in your area.

There is also Balboa RV in Van Nuys. Don't know anything about it. Our daughter lives in LA. When she was on the west side we always stayed at Dockweiler, now she has moved north, we stay at the Elks. There are several of those around if you are a member. The Simi Valley one is really good.

Nothing is close but 26 miles north is

Walnut RV Park Northridge California

Is is very nice - mostly permanents - I stayed there a week in Feb 2015 full hookups

Very nice swimming pool and clubhouse with laundry

Current rate is 315 plus tax a week ( 45 Day)

Anything within 50 miles of Los Angeles will be considered expensive.

There are some campgrounds in the mountains around LA... state and county most without hookups.

To stay close to Marina Del Rey your best bet is dockweiler.

Nothing closer... other options are at least 20 miles away but will be more expensive.