I purchased VueScan in 2016 for $40 bucks. It is a good piece of software, BUT now I am being forced to upgrade to professional, and the software I purchased no longer works. It now writes a watermark on everthing I scan.
I have reached out to support and have yet to get a response. The website says that you can download older versions, but the version I purchased is not on their website, even though versions from the same year are.