In the description you mentioned HP EliteDesk 800 G3 have i5 and 16gb ram but in screenshot description
sorry for my confusion when you say "All of them support NVME and 1 wifi/BT device.. So does that mean wifi/bluetooth adaptor/module built in?I was searching for it myself, couldn't find it either, I could find the i7 7700 for around 13.5K but not the T model. There is one available on eBay for 12k if you are interested.
Power Adaptors, Yes I have them for all of the units.
All of them support NVME and 1 WiFi/BT device + 1 SATA Drive
Display port cable, yes but not for sale