Since you've worked with the HU3 I'd recomend not going with the older Analog Bartech if you go the Bartech route. Go with the Digital Bartech, its a solid option when you can't get a preston and the Digital Receiver is tiny and quite helpful for Movi/Ronins.
For a single channel set up you can get everything you need for like $6k roughly. About $3k for the Hand Unit/Receiver and another $3k for a good motor and all the cables & marking discs. If you want a cheaper option to start with, you can get away with the Redrock Motor for like $700, so you can get up and running for like $4k or under.
I'd recomend getting your motor cables from Preston though, they seem to be the most reliable and sturdiest from what I've seen. Find someone to make all your power cables too, you'll save some money and the cables that come from Bartech aren't very good.
There's a ton of option out there, maybe some cheaper, but going with something with name recognition like Preston or Bartech will help you get the most money back on rentals from my experience.