Wife and I used https://freecampsites.net/#!(35.98489,+-121.48008) when we were van camping up and down the California coast. Lot's of hidden gems there.
We're back from our trip, but thanks for the site. I wish I had taken the time to look at it before we left. I was working elections that day (5am-9pm) and then we flew out the following day and just went with the plan we had.
After being there, driving around and talking to people, roadsides and parking lots are definitely can-do options for a van or small RV. There were about 5-8 vehicles in the Safeway parking lot of Carmel at 7:00 am Sunday morning, one of which was a jeep with pop up camper fully set up and taking about 6 spots, along with other vans or RV's that were definitely parked overnight. Even along route 1 in the Big Sur region, there were about a dozen vehicles that appeared to have been there overnight. Some pull off areas have signs that say 'no parking 11pm-7am' but others are completely unhindered. While hiking, we chatted with a woman that lives in Monterey, and she said there aren't any issues parking overnight in most places. Lesson learned if we ever do a trip like this again, at least in the off season.
As for the vacation and sights, thank you all for the suggestions! We ended up at---
Pescadero Beach-- our first view of the ocean when coming to the end of road intersecting with route 1
Ano Nuevo Beach-- wildlife preserve that has a significant elephant seal population
Natural Bridges-- Got to check out the rock formation, saw all the various Monarch butterfly clusters and hundreds of them fluttering about, stayed around for the tide pools in the afternoon
Henry Cowell Redwoods--- only had time for the main loop of redwoods before they closed for the day. Really enjoyed being inside the massive cavity of one.
Point Lobos Preserve-- managed to arrive 20 minutes before opening and there was already a line forming. One of the highlights of our trip! We walked around for 6 hours, watching seals and sea lions and dolphins, crashing waves and dramatic rock formations, sandy secluded beach areas, probably 2 hours exploring tidepools, whaling museum.
Pfieffer beach-- more stunning rock formations and purple sand. Exiting was a pain, since we left as the park closed, so the guards no longer restricted who was coming down the single lane road. There was a line of cars trying to get to the beach as another line of cars were leaving. Passing one car at a time is no big deal, but when there are 10+ cars all clumped together each way, it made for a very frustrating time.
Pinnacles national park--- So glad we spent 2 full days, one on each side of the park. It certainly would have been doable from only the eastern side, but really enjoyed exploring everything we could that was made possible by doing shorter loop hikes. This was one of our most memorable parks we've visited since the changes in landscape are so dramatic in such a condensed area-- the pinnacles, the caves, the reservoir/stream. We did see at least one condor, with its unmistakable color pattern from underneath, but weren't fast enough for a picture.
As for food, we mostly had our own. I did enjoy a large sampling of dumplings and buns from a SF chinatown place, some Lebanese for lunch, and surprising (to us at least) was the $9 lunch combo from Safeway.
Thanks again! This was a great trip for us.