Gretchen,
I read your post yesterday, and thought about it so much today. As I read all the replies others have given you, it seems like all the great advice is there! So I will only add what I have learned through the few designer bags I have purchased in the last six years or so(and they have been few!) My most expensive purchase to date is a Chanel I bought while in New York city with my daughter her senior year of high school. I have such great memories of that Chanel, and it is something beautiful she will someday inherit. But...do I use it much? No. It is not huge, so just trying to fit a small wallet, sunglasses, reading glasses(to read the menu, because of course that's about the only time I use it, for a night out, involving dinner) becomes a chore. So it is is not very practical for me. Most of my friends do not even know a designer bag. So if I do buy something new, I have only my family to really show it off to. But I do buy it for me, so it needs to fit my likestyle. Therefore, for you, possibly you might want the bag you can use daily, feel really comfortable, but not conspicuous. It should hold everything you need, and very easily--shouldn't a bag help you, rather than being stressful? I bought a
Gucci bucket bag this fall, and while I do love it, it is taller than wider, so hence, more difficult to get a wallet, etc out. In the spring, I bought a Gucci swing tote--very wide, and it is effortless to pull sunglasses, or anything out. My daughter bought her first upscale bag with her tax refund last year--a LV Neverfull, and she fills it with two phones, ipad, etc for work. And it works beautifully for her, and I know she is proud to wear it. So I guess what I am saying, the handbag you choose should be similar to your favorite pair of jeans--fits well and you find yourself wanting to wear it/them more often than anything else.
From my very limited experience of checking sites for pre-loved bags, LV and Chanel hold their prices so well, so if you only save a few hundred dollars by buying used, might it not be worth it to pay the full price and have the thrill of actually buying it from the boutique, and knowing it is pristine? I know this does not hold true for all brands(I would'nt want to call myself a liar, as I just today purchased a used bag on line, but paid $800 for a $2000+ bag--Chloe Baylee) but might be a consideration for the brands you are thinking about.
Others have their passions--not handbags, but boats, new cars, etc. so you are entitled to yours!