I have a 12 myself. Actually considering a 14 Pro Max refurbished from eBay, but my only hold out is I’d rather have a USB-C port. I can’t tell you how often my pocket gunk gets into that lightning port. I often see the worst of it in my car based on where I put my phone, the connection gets super sensitive and just moving the phone disconnects CarPlay often. I have the tools to clean the port out but it never seems to take care of the problem fully…
I was able to flash my Dreame D9 pretty easily. I had to use little wires off of a usb dongle which I got both off of Amazon. It looks like they sell a dongle on the Valetudo site specifically for Dreame devices that might be worth it in your case. https://github.com/Hypfer/valetudo-dreameadapter
I remember coming across a thread somewhere about creating an automaton to replace map files for different floors in your house but I can’t seem to come across it again. You could map each floor, export the file, then restore floor map files as you move the vacuum to other floors.