This is up my alley I'm a lead tech for CVS in southern CA, 30k is not easily achievable in retail unless you are full time and in a union. However most chain pharmacies do not offer full time positions anymore even if you are phenomenal as a tech since it's far cheaper to maintain a rotating level of part timers. Hospitals are easier to reach that goal with however but only super busy ones since the burn out rate is wayyyyyy higher in that environment. I've worked in both.

Anyway living in CA as a tech can be challenging depending on the job you get. Luckily my wife had the foresight to get us a manufactured home which we bought at 76k and after a year it's value has increased more then 30k+. Between the land fees and mortgage we pay about 1.5k which isn't bad. Even with limited hours we get by pretty comfortably but that's between two people and she works 40 hours also in retail (I still make more then she does with less hours) with barely any debt and no child.

Solo it's possible if you've got the luck with a great position and guaranteed hours but realistically it will take awhile to get to that sweet spot. VERY doable with roommates. I will tell you what I tell every new tech I encounter, stay in school and pursue something else, anything else even if it's one class a semester. The career path of a tech in retail is extremely limited since it's medical and highly regulated. However you have much much greater freedom in a hospital setting to branch into other things and but your license can take you somewhat far in the pharmacy sector in that setting.

So yes it's doable but hard. Retail from big chains do not offer much stability but you do get paid enough to get by most of the time. Do get your 401k started asap as well as stock options buy at the max give yourself a huge safety net while using your license to give you enough income to pursue a degree or other options. I'm currently working on finishing up numerous IT certs and plan to go back to school next year.