Yes, these are new products. You can find used / refurbished smartphones here: https://www.galaxus.de/de/s1/producttype/smartphone-refurbished-3326

I've just bought an OPPO A74 5G and I had the same question. The supplier wouldn't commit and told me to put in a 256 Gb card only. On Alibaba a 256 GB or 2TB card only costs 3 or 4 SFR. I ordered one of each (CHF 11 in total). The 2TB card is very well recognised in the OPPO and shows 2TB available... I tried to load the files on the SD card: --with Vice Versa Pro --FreeFileSync and --copying directly from Win10. I copied from win10 to Oppo and from win10 to the SD card reader PC. When you try to copy more than xxxGB at once to the card it creates a problem, the copy shows that the files are copied cleanly but then they are corrupted on the SD card and not everything is copied. But it's not the OPPO because the same problem exists when copying to the PC in the SD card reader. Copying smaller quantities works. When I've copied everything I'll test whether synchronisation works with FreeFileSync. I think it will work because I've been able to synchronise folders with fewer files in them (less than xxxGB). I'll be able to say more when I've copied everything to the SD card.

I have read about SDXC from 32 to 2 TB.