I have a few regrets but the items I never regretted buying (as pricey as they were) are: LV sunnies, Onatah Cuir GM, Mizi Vienna & mono pochette wallet.
denim patchwork speedy in blue, black neo cabby MM, mirage speedy in black, and mono speedy 30......I will never part with these bags!! I love them to death as they suit my lifestyle so much!!
The ones I use all the time and can't see living without are my cabas Mezzo, blace denim Neo Cabby and my bordeaux Mirage Speedy. I never carry my Damier Alma. but it was my first and I could never sell her. Then I have a few others that I sometimes love and sometimes think I should let go so I could purchase something new.
I always keep liking new things so I would probably sell any of my LV to fund a new purchase. Cept to sell damier 25 would be silly since I use it all the time...