There don't seem to be any problems with authenticity. What worries me is a Negative from a buyer unhappy with a bag's condition, and several "neutral" Positives that I know I've left myself for items I wasn't happy with but didn't want to go through the hassle of returning.
There's no proof but when a seller sells used Coaches all in one or two common colors, it makes me wonder if the bags are being re-dyed. Black is especially easy to retouch, and older black bags should show at least some wear around the bottom piping or a little color fading. But the blacks on her bags are all nice and evenly-colored and the turnlock brasses are nice and shiny - sometimes with older purses there's such a thing as TOO perfect. As I said, just a gut feeling. More opinions would help.
As for the second part of your question, shopping for older Coaches can be a minefield since there are more fakes of older bags than anyone realizes. Many of them are excellent quality both in construction and the grade of leather. Without knowing the basics about serial numbers it's strongly recommended that you only buy from shops that offer a 100 percent refund if the buyer isn't happy or finds out the bag is counterfeit.
Many older bags will have one of the known fake serial numbers from the Fakes List, but not all. Learn the basics of classic and vintage Coach serial numbers here:
http://forum.purseblog.com/coach-shopping/answers-to-authenticity-questions-94198-3.html#post1944848
and I STRONGLY recommend you print out the 3-post current version of the Fakes List, the list of some of the most common fake Coach serial numbers:
http://forum.purseblog.com/coach-sh...enticity-questions-94198-37.html#post18503288
posts 549, 550 and 551.
In fact if you scan all the posts in that thread you'll find a lot of information, although some of what's in the older posts is outdated and invalid.
Please take photos of anything you buy especially the creed stampings and post them here for authentication.