I don’t know if SD County currently has more “buyer demand” than normal. Non-resident people who wanted to retire here always did if they could afford to buy a home here.
As far as new household formations, I don’t see that here, but it may be happening in areas I’m not too familiar with. New Gen Y college graduates, even if SD natives are all aware that they can make more money in LA and SF in their chosen fields. I’ve seen not only my kid(s) but many of their HS classmates flee the county for college to never return, except for holiday visits. Many friends, neighbors and former co-worker’s children left CA long ago (either before or after college) and are raising their own children in other states (where they were offered employment). I’m not sure that the SD County HS graduate or college graduate “resident-retention-rate” is that great. Even though SD has a well-paying high-tech sector, other industries, especially state and local government and FIRE industry jobs pay up to 40% less here than for an identical position elsewhere in CA.
I think the typical buyer pool in SD County is more “well-heeled” than those buyers emanating from “new household formations” as most in this group are renters.
I think the vast bulk of SD County buyers of personal residences are comprised of households with W-2 incomes over $150,000 (whether already a resident or a “transplant,” these are the buyers using PM mortgages), former SD residents/natives returning to live near family (some using PM mortgages of all levels), out-of-county residents moving here (or moving back here) to retire (using all cash and poss small PM mortgages) and out-of-state residents and foreign nationals buying vacation homes (all-cash buyers).
Then, there is the investor-buyer cohort, which I believe is about 32% of all buyers (the vast majority paying all-cash).
No charts or published facts to go on, all just my own opinions.