AFAIK there is no Office Professional Plus 2019. MS Advertises:
Office Home & Student 2019 @ $149.99
Office Home & Business 2019 @ $249.99
Office Professional 2019 @ $439.99
For Office Professional 2019, see:
https://www.microsoft.com/en-us/p/of...%3aoverviewtab
If the price is too good to be true, it is...
That said, some of the prices you're seeing are most likely subscription prices for various editions of Office 365, which is presently equivalent to Office 2019. Or, they could be for pirated 'OEM' installations of Office 2013 or 2016...
And please also note the disclaimer on every page here:
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