Couple of places that I stayed at, neither of them in Modesto but not too far away.
I don't remember the exact name but right off the 99 just south of Stockton, it's something like Frnch Camp .... We lived there in our 5vr for about six months while our house was being built in 2005.
Another we stayed at is in Patterson next to the Amazon warehouse. Stayed here earlier this year in our MH. Probably wouldn't stay here for an extended period but was fine for a couple of days. This one is a Passport America park.
Neither are in Mo, but French Camp is probably under 30 min drive to Kaiser, Patterson would be a little longer but not too bad.
Chuck & Judy
2019 Entegra Anthem 44W
2015 Ram Ecodiesel w/AF1 and Excalibur