Suggestions for a 2-in-1 convertible laptop between £300-£500?

Looking around for a 2-in-1 convertible laptop for a budget between £300-£500 - anyone have any suggestions? I suspect I'd need to get a 2nd hand or refurbished one though since the good ones all cost a lot of money

Looking for it to have the following:
- 16GB ram
- 13.3" to 14" screen
- Preferably good keyboard
- touchscreen so can use it as a tablet
- Windows 10 is just fine
- Want to use it for some video editing as well so probably needs some decent processing power. I'm not fussed about getting the latest gen processor though!

I liked the HP Spectre x360 when I had one as a work laptop in 2016 but I'm aware tech has moved on quite a bit now.

Some others I've looked at so far:
Samsung Galaxy Book 360 Pro
Lenovo ThinkPad X390 Yoga
Microsoft Surface 5 or 6
Lenovo IdeaPad Flex 5
Dell Latitude 7400

Suggestions on a virtual postcard please...!