If you were a grad student at Wash U in St. Louis or at Duke, I’d definitely take a look at the markets there to buy, but you’re in San Diego and it’s not a cheap market by any stretch of the imagination.
As someone noted above, PI’s do move. My sister’s advisor almost went from NYC to LA. I have a number of friends who moved with their advisors (from NC State to Columbia, from UVA to UC-Irvine) What are you going to do then?
You’re a grad student. While I applaud the homeowner mindset, I still think there’s something to being flexible as a grad student. To rent one place and move somewhere else if you like a different neighborhood. Why anchor yourself at your age?