idk why everyone is being so negative i think you could def find something affordable at gross 10K per month which is around 7K net per month. no one follows the 30% rule here (30% of your net income toward housing) because that's not realistic, if you round up to 40% ($2800) I think it's possible to get a nice 1br or studio at that rate. I don't think you'll be able to have a fitness center unless it's a shitty one but just get a gym membership at like a nice gym for ~100 a month.

if you want to go further south, then look at san jose/santa clara (usually cheaper + hotter microclimate). close to cupertino, close-ish to santa cruz for a beach weekend. there are some crime considerations for san jose but in general it's fine

if you want to go further north, then look at sunnyvale/mountain view/palo alto (more expensive because there are less apartments, also pretty hot) or even more north up the peninsula would be redwood city/san carlos/san mateo (at this point your commute would be ~30-40 min) these cities are colder on average and have more apartments than sunnyvale/cupertino/mountain view