FLU. Sorry, I missed this when you first posted it. I don’t know the rental market up here all that well. I can say that I was considering renting out my 4br 2.5b in San Jose for $3,850/month, which is what the management company said I could easily get. Seems the rental market is pretty strong.
I would expect Sunnyvale to be higher than that and to be higher than Santa Clara, depending on what part of Sunnyvale you are talking about. I know my part of San Jose (West San Jose) is pricier than other parts, and Sunnyvale north of Lawrence and west of El Camino is the pricer part of Sunnyvale.
I will miss the diversity of the Bay Area and the rush of Silicon Valley. But I will be flying up here a lot to my old office. I have always flown to SD a lot from here and will just switch base camps.