Sounds like you got a good deal albeit with some TLC needed.
I have made a number of modifications to my BK3 which includes new motor pulley, new drive wheel for low and high speed operation, bearing based blade guides top and bottom, dust extractor fitting and a fence etc. I tried to post the link on your YT but this got blocked so have a look at altrish.co.uk and search on BK3. If you need any of the Fusion 360 files let me know.

Alan