The references to "budget line" were from contemporary sources, and that it was heavily reduced in cost - while terminal sequences were more of "simple matter of programming" ;-) My understanding that some of the features like changing cursor shape were related to the rudimentary custom font feature which was retained from more expensive 3xx line and which accepted IIRC sixel-encoded bitmap fonts.

Funnily enough, the one VT510 I had for some time actually came from a VHS rental place that for reasons unknown to me ran Blockbuster Video customized VAX 6.1 on Alpha (which I also grabbed). BBV was not very well known in Poland, but this specific machine had unwiped disks and logs showing it was used from 1996 to 2000, then it was found lying in a corner when a moving service was asked to clean out a location after a tenant that came in after the video rental.

There was probably a DECserver missing somewhere in the pile before I got my hands on it ;)