>>Now I'm curious what DELL.com will charge you ...
>>
>>
>>>>Those prices are directly from DELL.com?
>>>
>>>Nope... through 3rd parties.
>>>
>
>From dell.nl: 181,62 for the P1922H (without stand) including VAT

This might be a different VAT, we are at 19%

Ok, you got a cheap source for the P2219H
Cheapest P2219H without stand on idealo.de is around 133€. With stand 139€
600 Euro is a lot of money

On the other hand I think I would not like the high vertical angle of two monitors atop. I've played around with rotating my monitors a while ago and I found it not satisfying. To much up/down movment of the head. Left / right is much more easy. So a tripple 1920*1200 configuration, usage of Virtual Desktop and Powertoys will work. My 4k is more for after work usage . :)
If you have the chance, rotate the monitor you own and try to work with it for testing. Or try to borrow a second one and jury rig it atop.