I must say, I have to agree with much of what RedCatWaves says. This is why I refuse to spend big $$ for a simple moisturizer. Stuff like Cetaphil Cream, and the CeraVe products, and my shea butter-coconut oil combo are my friends and a whole lot less expensive than the hyped-up stuff with some "rare ingredient from the sea"/everything but the kitchen sink type of "feel nice, smell-nice" miracles creams. Don't fall for these, whatever one does! Even among very wealthy people who could well afford a lot of this stuff, either a trip to the dermatologist for that Retin-A, or a simple drugstore moisturizer is often what they do. All a moisturizer does is moisturize, period, and they really do help dry skin feel and look better due to the plumping action afforded by actually rather basic ingredients. I do rotate in a glycolic acid cleanser for exfoliation that works very well without trashing my skin, as my skin doesn't like leave-on AHAs etc.
The big guns that RCW mentions, however, are off-limits for many with sensitive skins, like mine for example. I'm inclined to agree about the retinols too, not enough difference to make it really worth it plus they dry my skin out, which I don't need at nearly age 65 now. In fact, I was reading not too long ago that by the time one is in one's 60s and up, the use of even retinols, let along Retin-A might have to be ramped down, if not let go, on account of the fact that skin becomes thinner and more sensitive in general(unless one naturally has very thick, resistant skin that's an oil well besides - there really are such people).
About sunscreens, I was just about to give up myself, as the all-chemical ones burn me, and the physical blocks tend to whiten me out such that makeup can't fix it, or have some really unpleasant texture, or make me break out. I'm not out in the sun that much anyway, and I refuse to smear sunblock thickly all over my body just on general principle. There are people who are so sun-phobic that they wear sunblock on their entire body even if they're not going out in shorts and a t-shirt/bathing suit. For me, I just have the CeraVe AM SPF 30 moisturizer, which I know isn't one of the industrial-strength type of sunblocks that people over on another board recommend, but at least it doesn't bother my skin. The others do.
As far as skin cancer goes, there are people who get melanoma who are almost never out in the sun, so the sun is not the only culprit - there's something else more systemic going on. Some alternative practitioners are saying that a person's diet influences a lot in this regard, in that the junk fats that many people are eating are present in one's skin, and react with sunlight, thereby contributing to skin cancers. They also put it out there that if one is clean from the inside out, from eating a largely raw vegetarian diet, the sun is much less harmful than believed. Still, even they don't advocate baking all day in the sun. Another factor that cannot be ignored - is that being so afraid of the sun causes a great deal of stress which also can't be good for one's health. Just respect it, it's a lot larger than you, like the ocean. Remember the old saying "Only mad dogs and Englishmen are out and about in the noonday sun" - meaning that it's wise to lay low then anyway, just like current advice says.