Personal experience
Maybe I got lucky but my 3 series vintage lambskin CF takes scuffs like a champ and I can buff them out no problem. Same with my Chanel caviar cardholder, which I'm pretty certain is one of the most hardwearing pieces I own. I also love the CF's 24K gold-plated hardware, which Chanel stopped using after ~2008. See the photos below from when I first received the bag and photos from after my DIY cleaning and reconditioning.
Resellers
Check Japanese resellers like Brand Off Ginza (where I got my bag), Amore Vintage, and Vintage QOO Tokyo for some more palatable prices. I spent a few months tracking down different Dianas in 2019 but then saw this CF and that was it for me. Dianas are pricer now but the Japanese prices still seem better. Patience definitely pays off.
Caveats
Leather quality changes by season so researching a specific season's leather quality could be beneficial to finally finding that near-perfect pre-loved beauty. Also, the older the bag, the flatter the quilts.
Happy vintage hunting!
Before
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After
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Before
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After
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