Question
There is alot of discussion on the Make-up Alley skincare board (do internet search for address). The consensus is definitely a very good sunscreen (daily) and a vitamin C serum. I am 27 and have started both the last 6 months or so (sunscreen on and off for years). Particularly in the short term the Vit C serum has made great improvements to my skin tone. I use the homemade version that is popularly discussed there.

Answer
S---Yes, they both can be pricey (if bought straight off the shelf in the store), but they last a long time.

MD Skincare Auto balancing moisturizer runsa bout 36 dollars for a bottle, but lasts me 3 months and I use it every morning. Instead of purchasing it at the store, I hunt for it on Ebay where I can get it at a MUCH better price---say about $18-22. You can even find bigger professional size bottles that are used for salon/day spa purposes pretty inexpensive.

Cellex-C for 30 ml or 1 ounce runs about 85 if you buy it off the shelf at Sephora or wherever, but on Ebay easily runs $45-50 a bottle and easily lasts me the same mount of time----3 months or so.

Say $70 dollars or so for beauty products every 3 months isn't actually bad at all---divide that by 3 months and you're spending about $23 hard earned dollars per month---which is Ok. It's not cheap, but it's not expensive either.

As for the Kiss My Face stuff, I think I pay about $6 dollars for a bottle and that lasts me a little longer---about 5 months.

Hope this helps!