I assume the Qnap DAS you are talking about is this one :

https://www.amazon.co.uk/dp/B07K23ZJFN?psc=1&ref=ppx_yo2ov_dt_b_product_details

I was recently in the same place as you and i’ve bought this… i have 2 x 16TB drives and 2 x 6TB drives in it all presented as individual drives… i’ve spent the last week syncing my data to the drives and it’s been faultless (this is a backup server for me)

I run Proxmox on a Lenovo USFF m910q and have passed the USB controller through to a windows VM running on it and file transfers max out the 1GB connection using rclone.

you generally will never get a letsencrypt for a freenom domain… letsencrypt limit how many certificates per day for each domain and the freenom ones hammer it.

I use BlueIris on a windows 11 Vm on an USFF Lenovo system… i’m running 5 1080p cameras on it with 24x7 recording an no issues.

My Vm is still working but i can’t for the life of me get in to my account… i keep getting emails to say it’s locked but i never receive the reset password email…