I'm no expert in this area, but here's how I'd calculate it:
Basically, you’ll be running from your house batteries. Van alternator, generator, solar panels – are used to charge your batteries.
Laptop - most probably use 100 watts or so. Unless you can get a 12v connection for powering the laptop you'll need an inverter. Inverters are maybe 90% efficient and some laptop power bricks get really warm when connected to Modified Sine Wave inverters. Heat is probably energy wasted in this case. So, conservatively, divide AC watts by 10 to get DC amps. 100/10 = 10 amp hrs. A Pure Sine Wave inverter would be better but it costs more.
(I get a little mixed up with amps, amp hours, amperes)
How many hours will you run it? How many days would this activity take place? I think you’ve mentioned that Chino will be working. (Chino has to take break once in a while!) 4 hours per day will take 40 amp hours from your battery. If you only have a single 100ah battery it'll be pretty much depleted. You're going to need more than one battery.
A cell phone won't use much.
Add lights, fan, pump, TV/DVD, C02 and propane detectors etc. to heavy laptop use, and you'll want to replace 50 to 60 ah per day. From info I've read, one 150 watt panel or two 80 watt panels should do it. Two 100 watt panels like what Cathy has on her Roadtrek should allow you to be independent of grid and generator power.
High voltage panels with a MPPT controller (costly) can give you more amps for your batteries than what the solar panels are rated for. Maybe 25% more.
The panel I purchased has a max amp output of 2.4. I'm more North than you so I can only really hope for 7 amp hrs per day from my small panel with a PWM controller. Maybe 10 on a really good day. My project will cost $300 (maybe $350 tops).
$5 per watt + a controller + bits & pieces + two new batteries to replace one older battery + inverter = $1,300 DIY (shop for bargains) average quality/performance to $3,000 good quality/performance (maybe all installed for you).
Lots of online sellers have RV Solar kits for sale. Here's one from Mr. Solar:
Some have kits that come with inverters.
You could of course combine a smaller solar array with some generator use. With a Class B you'll probably have to drive to get fresh water and empty tanks maybe twice per week when dry camping. Driving will also help recharge your batteries.