I live and surf in So. Cal. Most of the surf spots are very car accessible. Most some of the outlaying spots you walk to, not off road to. You do not need 4 wheel drive. If you go to Baja a 1/2 or 3/4 ton, 2 wheel drive will get you to the trade spots also.
If you are going to live full time a van is the call. I would have a way to seal the light off the front of the drivers compartment. You'll be staying in parking lots and campgrounds and a low profile living is what you'll be doing at times. There are some pop tops out there too. A RTT is putting a target on yourself. You will be cover camping at times.
I have had vans and trucks, the vans are easier to live in. Small vans are fine but board storage will be a issue , I would stay away from them. Trucks and SUVs are more for living out of. Keep the boards inside at night you don't want to lose them.
I had a van that I could turn into a bed from the back doors to just behind the frt. seats with a velcro attached curtain just behind the seats. Surfboards under the bed at night.
You can pick up a 2012 or so ford E150 for about 12 to 16 k and convert it pretty cheap.