My favorite state is California, I'd like to retire there as the weather is so much better than places like Florida. I used to live in a beach town in LA (Santa Monica) but moved because of the cost of housing and influx of tourists, it doesn't meet your criteria at all for those reasons--I also might add that beach towns south of LA like Hermosa and Manhattan beach have some of the highest housing costs in the US, so don't think they will suit your criteria. I'd think about northern California coast, like Fort Bragg, although it's getting more touristy, I think, but I've read that is pretty reasonable cost considering it's California. I'd like Mendocino but it's more expensive, which is why some are moving to Fort Bragg. You might also consider places in Oregon like Eugene or Ashland/Medford, they aren't on the coast but not far. I haven't been there but have read they might offer what you want. Having known several people from York, the good thing is just about anywhere is a step up. If you are serious, there are sites and books to research on this subject; Rand McNally publishes several city guides with stats on all facets (called Places Rated) and might be at your library if you don't want to buy it. At age 30, though, I might look more for good job oppotunities and reasonable rental costs than some other stuff. In that case, southern California does have much more reasonable rents (compared to other big cities) than you'd expect in comparison to the cost of buying a house. Really, your profession and potential income really have to be factored in here if you're only 30.

There are some great towns along the New Jersey Shore such as Spring Lake, Brielle, Brick, Sea Girt, Bay Head, Red Bank, etc.
Nice beaches (they really are for those who have not been), close to many all-year employment opportunities and a beach season that runs from May until late-September.

For culture, you are about 90 minutes from New York City, there is a year-round community in many of these towns, and while there are plenty of tourists, many parts are not overly touristy.

Some towns like Spring Lake, still seem like a small, 1950's village. Yes, the home costs in some towns can be quite high. However, there are plenty of apartment rentals and townhouses for rent within and near many of these towns.

Well, I would go with the Olympic Peninsula in Washington state. Sequim has one of the most perfect climates in the U.S.--it feels like May about 7 months of the year and roses bloom until December, take a brief hiatus and start up again in March. Lots of sun and clean air and yes, the housing is (still) affordable. Fabulous beach walks and you can actually swim in the water at nearby Marrowstone Island (plus Sequim has a great aquatic center). Culture, not so much, but there's plenty of culture down the road in Port Townsend, with its variety of summer music programs, renowned writer's conference, jazz bars, visiting artists programs and so on. The OP rates pretty low on the tacky scale.
We're living in Europe now, but when we move back to the states, we're making a beeline to the OP.
The only problem I see for you is how you plan to make a living...what do you do? If you're self employed or work in the healthcare professions, you could be ok (or if you're a highly skilled carpenter or other high demand craftsman). You didn't mention how you plan to support yourself in your message--if that's not a primary concern, good for you!
BTilke

I live in San Clemente, CA, which has been mentioned by several people. I would say that it fits all of your requirements except cost of living. In the context of Southern California it is comparatively reasonable, but take that with a grain of salt! The attractive parts about the area are the weather and the small-town beach community feel (which is, unfortunately, being impacted by development). The primary negative is that we are far enough south to be a pretty good drive from most employment. However, my husband and I think it's well worth it. Check it out if you are looking for a change!

BTW, I love San Diego, and would live there in a heartbeat, but if you look seriously there, do some research on where you would work before you commit to where you would live. They are a little late in developing the transportation systems to support the growth that has occurred, and daily commutes are rough.

Grew up in Ventura, CA. Beach town to the max. Everyone spent summers lounging at the beach in the fog or the sun. Didn't buy a coat until I moved to N CAL. May not be all that culturally fulfilling but there is some going on there. I live in CA so I know nothing about affordability according to non CA residents. No perspective at all. We pay outrageous amounts for housing, electricity and gas (but it is getting better, and no blackouts!)

I'd tell you, but then I'd have to kill you, because I don't want anyone else moving there. Hint: You can drive there from York.