Are you also planning on buying a gym membership for showers, etc? Your biggest problem will be dealing with dumping your grey and black tanks. If you get a van with a cassette toilet, you can remove the toilet tank and dump it in a bathroom. Sportsmobile also makes a unit with a toilet that burns waste and turns it to ash.
Diesels are more expensive to buy and maintain. You get better mileage, but if you are mostly going to be parked, a gasser would probably be a better fit. The only new short gas RVs are based on the Dodge Promaster chassis, but you can find used Chevies and Fords, as well.
You don't need much in the way of air conditioning in San Jose and since awnings and rooftop AC units are giveaways that you are in an RV, you might consider getting a custom build from Sportsmobile that deletes those items. Unfortunately, they have a long lead time.
Because of the noise, you won't be able to use a generator for your 120V needs so you will need a big battery bank and an inverter, an underhood generator and, possibly, solar.
The light leakage will still be an issue, but I don't know how much the police care - you aren't alone in your housing dilemma. Some homeowners may complain, though. I've heard some resentment from those who pay property taxes regarding people who live in the area but don't pay those taxes.
To be honest, I think your best bet is to rent space next to a house where you can plug into their shore power and be off the street. That would solve your battery/power/generator issue and the light problem. It might also be a place where you can leave your dog while you are at work - vans get hot.
A new Ascent is about $100K - you can look on RVT.com for current new and used prices. Without knowing what other issues may arise from your plans, you might want to buy an older, used RV and see how it goes for a few months before committing.
2018 Coachmen Crossfit/Beyond