If I had the money... Spokane throughout the summer, central Florida during the winter.

Don't know about Spokane, but summer would probably be somewhere on the West Coast, northern New England, or higher altitudes in the Southwest (e.g. Santa Fe). Winter is harder but, assuming I was trying to avoid snow, probably somewhere broadly in the desert Southwest.

Sounds like you could minimize travel then by say, Flagstaff and Phoenix, respectively?

Personally, I'm generally fine with snow and cold but but, yeah, if you're looking for fairly temperate climate year-round, it's mostly either California coastal areas or shifting between the lowlands/highlands in the Southwest. As you say, Flagstaff and somewhere in the Phoenix region would be a good example. Probably are examples in Colorado and New Mexico as well. Vegas in winter is also an option many like.