It's actually a $200 difference between 12 mini 256 GB and 13 mini 256. I feel like the 12 mini 256 GB that I found at $530-550 is a good deal, condition should be basically like brand new with no scratches on screen or camera. I only care about the camera, and it seems like it's only slightly improved on the 13 mini.

Battery, if it lasts longer during the day might be nice, but really if it just lasts from the time I get up to the time I go to bed, that's more than enough for me, since I'm used to connecting the phone to charger when I go to bed every night and unplugging it when I wake up. And it sounds like the 12 mini should do this, since I don't use a phone too much - I don't watch streaming videos for a long time, I don't play games on a phone at all (I use an Xbox for that, that I only use occasionally), I might remotely access my computer at home if I'm away from home for a little bit but it rare or access a virtual machine running on a virtualization server at home or in the cloud from the phone but that's also rare. I use my laptop most of the time throughout the day and not a phone so much. Phone is nice for small things like alarm clock, calendar and to do app notifications, and quickly reading and deleting most emails and archiving a few.

So it really sounds like 12 mini 256 GB is the way to go for me at the price. But I'm seeing so many comments suggesting to go with 13 mini that I'm tempted to do that.