Kenneth Jolly, 54, will be subject to supervision for a further three years after his release and his name has been put on the sex offenders register.
Jolly, of Forfar, Angus, picked up vulnerable young women in Dundee and took them to a caravan on the outskirts of the city, where he subjected them to sexual attacks.
After a jury trial last year, the mechanic was convicted of raping one woman and indecently assaulting three others. The case was adjourned for background reports.
All of his victims were heroin addicts, the High Court in Livingston was told. Frances Connor, defending, said Jolly – who is being treated as a suicide risk – had lost everything as a result of his crimes.
She said: "He had a nice house, a good job and a loving family. He recognises that by his actions he's destroyed all of that, and that's something he has to live with."
Jailing Jolly yesterday, Lord Boyd said the gravity of the offences meant each one on its own would have merited a trial in the High Court. He said: "They are separate crimes on separate occasions. In cumulo you'll serve 12 years of which nine years is custodial."