The home button no longer works (I use the on-screen AssistiveTouch for past year), I am out of the "support cycle" for iOS updates (although still getting some security updates), and DW isn't happy that my phone is so slow (we mainly use my phone when we go out, and DW likes to leave her phone at home).
I do use the camera fairly regularly for my work, so that is important to me. Additionally, longer battery life is always good, as the batteries invariably start to work less well over time.
Further, it looks the new iPhone 12 Pro Max is only ~3 mm or so taller than the iPhone 6 Plus:
iPhone 6 Plus dimensions from https://support.apple.com/kb/sp706?locale=en_US :
iPhone 12 Pro Max dimensions from https://www.apple.com/iphone-12-pro/specs/ :Weight and Dimensions2
Height: 6.22 inches (158.1 mm)
Width: 3.06 inches (77.8 mm)
Depth:0.28 inch (7.1 mm)
Weight: 6.07 ounces (172 grams)
I'm pretty confident that with 5G support I'd probably keep the iPhone 12 Pro Max for another 5+ years. I won't get any discounts (Verizon offering $23 as trade-in for my iPhone 6 PlusHeight: 6.33 inches (160.8 mm)
Width: 3.07 inches (78.1 mm)
Depth: 0.29 inch (7.4 mm)
Weight: 8.03 ounces (228 grams)

iPhone 12 Pro Max:
256 GB, $1199 + $199 AppleCare+ = $1,398 = $279.80/yr over 5 yrs
512 GB, $1399 + $199 AppleCare+ = $1,598 = $319.60/yr over 5 yrs
I did look at Apple Certified Refurbished store also to consider other options https://www.apple.com/shop/refurbished/iphone . They have a refurbished iPhone X 256 GB for $679.00 https://www.apple.com/shop/product/FQA8 ... d05c8bdbc3 . Release date 9/2017 so I'm assuming I'd be able to use for 3? or so years.
iPhone X Certified Refurbished:
256 GB, $679 + $199 AppleCare+ = $878 = $292.67/yr over 3? yrs
For iPhone XS Max Certified Refurbished https://www.apple.com/shop/product/FT5D ... d05c8bdbc3 . Release date 9/2018 so assuming would be able to use for 4? or so years.
iPhone XS Max Certified Refurbished:
256 GB, $849 + $199 AppleCare+ = $1,048 = $262.00/yr over 4? yrs
512 GB, $1019 + $199 AppleCare+ = $1,218 = $304.50/yr over 4? yrs
Looking at above per year calculations, it seems that iPhone 12 Pro Max 256 GB would probably be way to go. Any thoughts or other ideas?
I realize USED phones are available through swappa.com and such, but I'd be hesitant to have a used phone without an Apple (or similar) warranty.
Thanks!