Have you had a Cali sized camper before, or are you coming from old fashioned camping with a small tent? If not, I'd hire one on a wet cold weekend first. Alternatively, the family can spend a trial weekend locked in your smallest room (en-suite bathroom) with wet coats and a wet dog. That should help establish if it's for you all.
Do regard this as reasonable advice, not anti-Cali. I've had them for 10 years, but know their limitations.